Does your site need to have original content to use Adsense? I've seen some sites that just republish publicly available press releases and slapped on Adsense on it, is that legal or a violation of TOS?
it is legal, and many people are doing it However, they shouldn't rank well since the content is dupcliated
You can use any type of content with adsense. But google and other se's see the content as duplicated and just do not rate the site. So the mantra of the so-called gurus "Content is King" is a bit flawed as those gurus never tell you it should actually be "Original Content is King". If you use other people's content, reword it-rephrase it-make it a bit more unique to your site. One big drawback to using articles where the author wants you to keep it as is with his links. Find a good source of articles that will allow you to do the reworks.
yeah...i've read an article that if your site is just a copy cat... Google will not approve your adsense application