Can I just copy and paste content from Wikipedia to my site and backlink the article to wikipedia? I read there TOS, and from what I understood, it is ok to copy the content Now, what I want is to create a database using the content from wikipedia(relating to my site subject) and display it in a different format on my site. I think it'll be ok, just want to know ur opinion! Any help will be appreciated.
Yes you can do this, just make sure of the backlink. But dont expect any real traffic, from experience wikipedia articles is not real good at bringing SE visitors. (I think you can even use it without the backlink if you list at least 6 of the authors or something like that, if I can recall the TOS correctly)
I disagree with that. I find that when I'm doing research for classes in school I will almost always come across a wikipedia link in the first 5 hits for a search. While yes, creating duplicate content sites will not drive traffic, search engines drive A LOT, if not all, the traffic for wikipedia. A duplicate site will not get nearly the same search results because of pagerank effects and other search engine methods. If you meant specifically wikipedia articles on dupe sites, then I would agree with it.
All wikipedia content is licensed under the GFDL which you can read about here: http://www.gnu.org/copyleft/fdl.html. Wikipedia content has been replicated on so many sites though that you're pretty likely to get labelled as a duplicate (or just low down in the results).