GTA, although 4 was let down for me, before that the series just got better with each release. The pinnacle being SA
GT, i still wish for damage instead of time penalty though
Quake, i have loved and made levels for quake from the very start but Quake 4 like doom 3 was an utter fail. both forgetting what made them great in the first place
Deus ex, OK so invisible war was no where near as good and Snowblind was not official (although it did start out as an official Deus ex game) i love Deus ex more than any other game and cant wait to see if three is a return to form.
Metal gear, I've played this since the ps1 classic and although i think 4 is great, snake eater is the high light for me
Worthy mentions, Toca (now grid), Soul calibur, Tekken and Wipeout
assumption is the mother of all f**k ups
