Right now (pending announcements by all three console manufacturers), Microsoft has the "core" better covered than anyone. GeoW2, BK: N&B, Fable 2, Too Human, Halo Wars, Left 4 Dead etc. The ONLY way they could sound desperate for core gamers this holiday season is if anyone of the first five titles I listed were delayed. That, I admit, would be problematic.
All Microsoft needs to do at E3 is show off their industry leading core titles and do everything possible to bring in some non-core gamers.
starcraft - Playing Games = FUN, Talking about Games = SERIOUS