Battlefield: Bad Company
Absolutely sucked me into mutliplayer FPSs. Before I played some Socom, Battlefield 2: Modern Combat, but I never became absolutely passionate about them until then.
I don't know if it only counts as games released this gen, but Medieval: Total War got me into management based RTS (I just autoresolved), but Rome: Total War actually made me enjoy the real combat and tactics aspect.









