easily you can get on the first page of google with .info domain presuming there are no already established .com/net/org sites for the same keyword or you can get the first page of google with .de/fr/it etc country domains for users searching google from those countries, in which case regional domain will have advantage over generic .com/net/org
It is certainly possible (do a search for plug and play niche cash in google). I think a lot will depend on how old the other domains are, how many backlinks they have, which keywords they target,...
i agree with atxsurf,it depends on the number of backlinks and the targeted keyword too...it is posible
It's possible, but the odds that an existing .com, .net and .org haven't already SEOed the hell out of a quality keyword are pretty low. Google doesn't have an inherent prejudice against any particular extension unless that extension is a mismatch for the language of the query. For example, a .ro domain is going to underperform for most English keywords. But, a well-SEOed .info will blow a poorly SEOed .com out of the water.
This is another of those questions that have been exhaustively discussed time ago. However I should say that if someone has the dot com parked or underdeveloped, it's more likely the following extension or that with the best content rank better, and if this is in the same condition, the following, and so on. In fact I have seen tons of dot coms dismissed just because of the parking/non-content issue.