Lack of mouse/keyboard support is the only reason I refuse to play any FPS on a console. There is no debate, M/K is far superior to a gamepad for FPS games, but can also have advantages in dungeon crawlers, such as Diablo III, and virtually all MMOs can have a huge benefit. M/K support would allow games like World of Warcraft to come over to consoles without much effort. RTS games like StarCraft would be viable.
These console companies and their game manufacturers don't seem to focus on just how much better a console and the gaming experience could be....instead they focus on crybabies who don't want to ruin their "gamepad" experience. In reality those are few and far between. True gamers know that a M/K is far superior.
The money these companies can make, the merging of the PC and Console gamers, the advanced controls for complex games, all leads to money in their wallet. Why do they still advocate against M/K support makes no business sense.