I saw today on E3 that Four Swords will be released for free later on the DSi. Does that also count for the 3DS? Because my friend and I are really wanting to play that together, and we both have 3DS' and no DSi's.
It will not be on both of the stores. It will be DSiWare. That being said, Ninty is putting the best DSiWare on the eShop channel, so it's highly, highly, highly, infinitely highly likely that we'll see it there.