I always add a quote from our President or another individual relevant to the topic of the release. Often, the formatting of PRWeb.com and other sites 'pull' these quotes to format the release. It also validates the content.

Choose the right time to send out a press release. Sending it on a Friday at 5:30pm would probably not be a good idea. Perhaps send it so your target audience gets it on a Tuesday morning. Also consider the time zone of your target audience.

It is incredibly important to include links back your website with keyword centric anchor text but don't over do the number of links and make sure you are mapping your links to the appropriate interior pages on your site. Search engines dilute link authority based on how many outbound links are coming off a page, which is why it is best practice to keep the number of links on a press release to 5 or less. Another common mistake companies make is pointing all the high authority PR links back to the homepage. Spread out your link distribution so that interior pages optimized around specific keywords gain more authority and move up the rankings. Not everyone wants to see your homepage if they're looking for something specific.

Great addition Victioria, timing is critical as with email marketing. Not just when you send from a calendar perspective, but also from a current events perspective. If you have a new product or service related to a current even, there is a good chance you will get the ear of a journalist. Second to this would be establishing those relationships with journalists, both locally and in your field.
My addition would be

Sorry for error in the above post. You can edit out the last fragment "my addition would be" (I didn't see it until after publishing).

Nice coverage of the basic SEO/technical tips -- and a great new tool, too!
It's a little fuzzier to "grade," but a press release should also "say" something about the company. Not sure how you grade substance, but the "gobbledygook" meter is a nice touch.
And don't forget spelling and grammar!

Add additional background links in a multimedia or reference section. For example, a press release about a new MP3 might contain a link to reference material about what an MP3 player does or to a del.icio.us page with bookmarks. This makes it easier for reporters to write a story and helps customers reading the release because you have provided the research for them.
Include social media badges or links so people can add the press release to digg, del.icio.us, etc. and drive visibility.

There are many other suggestions for effective press releases, but you said basic. So basic it is, please don't forget to start a press release with place and date of release ;)

Another prize I'd propose you give is to someone making ALL the rookie mistake you list :)

Stellar article (does anyone say that anymore?) Anyway I remember when I did my first press release as a newbie...it was designed to shine attention on a spankin' new controversial free eBook I had just launched...
Well the big mistake I made was to host a downloadable copy on PRwebs website and although it gave me incredible exposure I couldn't figure out why despite the many thousands of views I wasn't getting more people clicking through to my site to subscribe to get my eBook.
This was a classical Duh moment when many months later when I was a lot wiser and had more time on my hands to think properly I figured it out!

After reading feeds every morning, selfishly, this might be the most important:
Have something newsworthy to report. Don't issue the release if its not news. It won't get read.
Here is the latest one I saw on prn ("x"s substituted the actual characters):
Industry-Leading xxxxxxxxx Cost Management Software, xxxxxxx(R) Select From xxx xxxxxxxxxxx xxxxxxxx Attains xxxxxxx Compatible Product Designation
Beyond a very windy title, the topic won't generate any interest. Announcing a partnership might.
(Donate my winnings to charity!)

I'd like to put out a press release for my lovely daughter who is graduating from High School this week with a 4.29 GPA (co-valedictorian of her senior class), and was just accepted to the University Of California at Berkeley class of 2012 (she was interviewed by Harvard, but didn't make the final cut).
What's newsworthy about this information? She's also one of my best performers (she is a singer, dancer, and co-emcee for my company), and was recently hired by a Murder Mystery company in the Bay Area (owned by a DJ friend of mine)-- so she's already got a part-time job waiting for her .
I'm going to post this at Yelp (local sacramento board), and maybe also on my Merchant Circle page.
My name says it all.......LOL

Great basic press release tips. I also think it is important to include quotes in your press release - something easy to do.
Additionally, attaching images, podcasts, videos, etc. (super simple if you already have these materials) will really help improve pickup/rankings, make the release more interesting and give reporters/ other sites additional resources if they decide to pickup the story.

Is it true that you're more likely to get your Press Release published if you include a link to a picture that goes with the release?

I believe it often is true. If you submit the release online through a distribution service like PRWeb, you can attach the image, video, etc right on the release - it makes the content more interesting and can also show up in universal search results.

Comfortable in the gray? Bring together the best of SEO tags and the quotes (especially if it is a new me-too product or service). Have a quote mention a major, public player by name. So if you have a shopping site, one of your shoppers can be quoted saying that the search functionality is as easy to use as Amazon. Then all the search engines pick up on Amazon and you get play well beyond the value of your me-too. And since it is in a quote that compliments copyright holder, then they tend to be less irate.

Great article!
There is a very easy to use and inexpensive ($20) tool available for optimizing your press release for search at www.newsforce.com. If you are a Business Wire customer you can also find it as part of their EON suite. The tool supplies keyword analysis data and a wizard interface that tells you exactly how many times to repeat the keywords and where to put them. You even get a ranking report at 3 different time intervals after you send the release over the wire telling you exactly where it landed on the search engine results page (and you get an actual screen shot of it).
The best part is that you don't have to be an SEO expert to use it.

I've done a quick survey of the publications that our press releases regularly run in. No one uses links in the body of a release as its being described here. We're in a very niche B2B market and I don't know how this will go over with the publications. Anyone else have any experience in being the "first" to start using a new format?

Feature request: I think it be helpful if Press Release Grader analyzed the structure of the first paragraph of the release -- looked for date of release, location, and company name. Other points that the first paragraph should include are the type/why of the release -- product release, partnership announcement, etc. If there is some way to grade this too, that would be an added bonus!

The subject line is definitely of importance. Using words like "free" in the subject line can hurt deliverability while including your company name can add credibility. This is the very first thing people will look at when your release is considered, so it should most definitely be considered in the score of a release.

Two things:
1. Keep your press release headline short but informative. No one wants to read a long headline, it foreshadows a shallow release
2. As important as it is to not release on Friday at 5:30, do your research on when release activity is active but not overkill. Sometimes Tuesdays are the worst days for that very reason.

Great tips! Re: the gobbledygook factor, have someone else ready your release, preferably someone without too much industry knowledge, and see if they know what you're trying to say.
They can act as a proofer, too, for spelling and grammar since your eyes may gloss over mistakes if you're writing and proofing!

Additionally, it is beneficial to have a short pitch at the beginning of your e-mails to editors and the like. This pitch is a quick synopsis of what the editor can expect. This not only helps make sure the information is relevant fast, it aslo assist the editor, and we all know that building a good relationship with the media is of the utmost importance. Thanks!

I have a few tips from an editor's perspective. Include a phone number that is intended for readers to contact the company. Many press releases only include a phone number of the P.R. representative for the reporter to call. 
 
Limit quotations to what is newsworthy. Cut out the flowery fluff.  
 
Put the attribute to a quotation at the beginning of the quotation or at the end. Don't break up a quotation by putting the attribute in the middle and having to start the quotation again. Newspapers never do this, which means that the press release has created more work for the editor who has to fix it. 
 
Write your press release using Associated Press style, which is used by most publications. Otherwise, you create more work for the editor. 
 
Let's say you are sending your press release to a lot different categories of industry publications. Tailor separate press releases for each industry you are trying to reach. 
 
Don't put your press release in a pdf. format since it's harder for editors to work with. 
 
Always put your press release in the body of the e-mail even if you are attaching it.  

When I send press releases, I include my cell phone number and the note that I it is available 24/7 --and then I honor that. Reporters work long hours, and they appreciate and remember someone who makes themselves available evenings and weekends for interviews and to provide additional materials, if needed. Also, let them know in the press release if additional materials ARE available -- high res photos in digital format, b-roll footage on beta, etc. It shows an understanding of their needs and it shows respect.

you forgot the most important part--make the press release INTERESTING with a catchy title so all your efforts will result in someone actually READING it and REMEMBERING it.

Great comments. They sure dispel the myth that "anyone can do PR."

I always include one or two quotes from people within the company that are specialists on the particular press release subject. This highly increases the press coverage of teh press realease.

I'd like to add a criterea.  
 
 
 
Construct the release in such a manner that it is informative, but leaves the reader wanting more. Hence, they will be inspired to investigate, speculate, hypothesize, etc. This is also where the contact information becomes of use, that is, your press encourages the reader to engage in an active role. 
 
 
 
Just my two cents.