PS3 is getting most of my hours at the moment due to GTA IV. The Wii had previously taken most of it and gets the award for most-played by me for this generation. The PS2 probably has the best game selection of any console EVER and it will not be beaten anytime soon. That sort of market dominance will likely never happen again. That said, I feel happiest when playing my DS. I REALLY wish more adventure titles and RPGs would release for it in the US. However, I am going to Europe this summer and plan to buy a ton of games that just are not released over here--can't wait to learn German!!
