I think Modern war based games will eventually lose there appeal, the same way WW1, WW2 and Vietnam war games have slowly died out. The FPS genre in general though will not lose it's appeal as long as games like Halo, Bioshock, Killzone, Half Life etc just keep changing things around to keep it fresh.
Bet with Conegamer and AussieGecko that the PS3 will have more exclusives in 2011 than the Wii or 360... or something.