I've been playing Lost Odyssey. Turn-based role playing games with random battles = I'm in love. I think a lot of people are turned off by turn-based rpg's anymore, but seriously I can't get enough of them. And the story and graphics are great so far.
Right now, it would be Mass Effect - followed by Halo 3. ME is an amazing game, Halo 3 is pretty good, too... I think Devil May Cry 4 or Lost Odyssey would beat it though. Amazing looking games. Oh yeah, I plan on borrowing my sister's boyfriend's Call of Duty 4 soon... can't wait.
Ah man I really want to try mass effect. its next on my buy list. I am really looking forward to, too human as well, it looks like everything hellgate london said it would be and more.
Armored Core 4, I guess. It stands up well enough to the series. You have to like hard games, and the mecha.
My favorite game of all time is now Bioshock. Loved it soooo much I played it twice in a row, the secord time being on hard. Beautiful graphics, awesome music, colors, characters, etc. It is just so good at setting the mood and controlling your emotions. A must see for everyone! Right now I've been playing around with the Orange Box which is good as well. Team Fortress 2 is pretty fun to play online....