As for the gameplay, its a little hard to describe. The camera is set in the traditional RTS perspective, but it wouldnt be fair to call Dota an RTS. And while each hero starts at level 1, and many times hits the level cap of 25, it wouldnt be fair to call it an RPG.
Lots of people have tried to assign various genre names to Dota, but we think Action RTS is probably the most descriptive. And while we dont spend a lot of time trying to figure out what genre the game is inventing, we cant stop playing it internally!