If you do the right things to develop and promote it, the TLD should not affect SEO. However ... and it's a BIG however ... with a "backwater" TLD it may be harder to do those right things, so SEO could be undermined by indirect factors.
When someone else controls the .com versions you can expect that users' ingrained dot-com habits will cause your promotions to drive traffic to your competitor. Maybe a little, maybe a lot.
Also, you may have trouble getting other webmasters to view the domain seriously (harder to get links), because they take the .info domain as evidence that you're a johnny-come-lately.
It only costs a few bucks so grab the domain if it's still available. But I'd urge you to keep thinking and come up with a name where you could own the .com.
Remember that intelligent use of keywords in file paths can go a long way to matching the presumed advantage of a keyword domain.