First off, you don't tilt the world to move your guy around -- one of the defining aspects of the PSP game. Also, you don't directly control the Loco Rocos, instead you control what appears to be one of the flying fruit bugs from the first game and use it as a cursor to direct where you want your Rocos to go. In addition, it appears to be based more on moving around batches of Rocos instead of absorbing them into one giant Loco Roco.
With completely different gameplay, it's going to be interesting to see if Loco Roco can achieve the same following as the PSP one. We should find out soon though, as the game is rumored to be coming out in the next couple months. Any hardcore Loco Roco fanatics out there? If so, what do you think of this footage?