I think that FFVII is one of the worst games in the series.
FFVIII is one of my two favorite games of all time. (The second being Rogue Galaxy. Which reminds me, I hated the Dark Cloud games with a passion.)
There are only three things I like in FFX (everything else I hated). In no particular order they are Auron, his theme, and blitzball.
I adore the pants off of FFX-2.
I love AC2, Ezio is one of my favorite characters in video games. That being said, I returned Brotherhood to Blockbuster about an hour or so into the game. I bloody hated it.
I think the first Halo is merely sub-par, didn't like 2, and refuse to play any of the other games in the series.
I can't stand God of War or the Prince of Persia games. (Yet I loved the movie)
I don't like MMORPG's with pretty graphics. Something in my mind just won't accept them. I expect my mmo's to be ugly by modern standards.
I didn't find Human Revolution interesting enough to be bothered to finish it.
I returned Dead Island to GameFly about an hour into Act 2. I don't regret it.
I would be perfectly happy if they never made a zombie game, movie, book or whatever ever again. Unless it started with the title Resident Evil, and was an actual survival horror game. (On that note, I think that Resident Evil 4 was an embarrassment and should have the Resident Evil stripped from it's title.)
The most fun I have ever had playing a game online was with 007 Rogue Agent on the XBOX.
I think Deus Ex: Invisible War was a fantastic game.
I claim to hate stealth games, yet can't get enough of Splinter Cell or Hitman.
As a side note, I disagree with Yahtzee, it isn't a jet pack that could make every game better. It is a grappling hook. (Evidence can be found in the new Bionic Commando and in Just Cause 2).