The 360 may be more mainstream, but that's because Microsoft just always throws crap out onto the market to get there product out there first, and chances are Kinect will have a whole bunch of errors with it, and the crash and burn. The ps3 Move will more then likely just get ignored. Then you can tell Sony produces better products, look at the Ps2, they are still making games for it, while Microsoft's Xbox is literally dead, and not even Gamestop sells games for it. The reason why Sony wasn't in a rush to release the Ps3 is probably because the ps2 was still selling really well.
When it comes to games for the PS3, if you really did have a ps3 you would be able to compare games to the 360 games. For example the ps3 equivalent of Halo is Resistance, and both are good games. Halo is just a lot more overrated than Resistance. Then there are plenty of other good titles for the Ps3 if you look. If you go to Gamestop and look at both walls they will have about the same amount of games, and plenty of the same games since most companies now are making games for more platforms.