At first, I was only focusing on the free press release distribution sites, but just about all of the top press release sites are now Freemium services–meaning free for something not so great, but paid if you want the real thing. BusinessWire has now introduced its budget priced EON service, or enhanced online distribution, so it is now competitive with the others.

BusinessWire also has the highest PageRank (8), and Warren Buffett owns the company, so it might be worth looking into.

I combined the Mashable press release distribution list, plus a bunch of other lists, and then did my own Google searches to put together a definitive list of press release distribution sites. Then I checked every site to see that it was actually a press release distribution site. I cut out the sites that were closed down or taken over by spam sites. Here is the mega list.

The sites are ranked by Google Page Rank (higher is better), Compete.com unique monthly users (more is better), and Alexa rank (lower number is better). Please leave a comment if this list was useful, or if you find something that I missed.