The reality is TimeShift just wasn't hyped up as much as titles like FEAR. If you look at how rapidly the FEAR forums declined even after the first expansion and free release of Combat, it is clear that the public wasn't getting enough out of the game to make it long term playable despite the initial success and marketing hype.
That's true. FEAR seems to have all but vanished from the collective memories of gamers. ;) Of course, it was a system killer when it launched, but the 8800 series completely destroyed it. Max settings, no problem. ;)
Bioshock is another game that I think left the collective memory of gamers quite quickly. Sure, there are some people that are still talking about it (and the release of the patch - finally - had something to do with that) but overall I think after a short period of initial hype (and bad press) the game all but vanished.
Man, with opinions of TimeShift being so polarised... I think I'll be adding this to my Christmas 'must buy' list. ;)