I've always believed that by sending out Press Releases through an online service (PR.com PR Web etc) was a great way to get back links & traffic through the actual PR and articles written on the PR (ie through link bait). I understand that you can't over saturate them, but I've always felt that a few Press releases a month for newsworthy info was a great SEO practice? Any thoughts on the subject? Disagree? Experiences? Success?
At this stage in the game, buying backlinks is a big no no. They're being devalued as we speak, and I'd rather natural articles and backlinks anyway.
Press release IMHO are a great way to get links, and get your message out there. I have sent out 3 press releases so far about my site using the free press release services and 2 out of the three made it on page 2 for my keywords outranking my site itself.. they are legit, easy to write, and can act as good advertising if a user stumbles across them. Would I pay for them however? Probably not for my little site.