Tracked time: 210 hours for Fire Emblem Awakening

Untracked, Age of Empires II, probably at least 600+ hours

I played Destiny for about 190 hours but I'm pretty sure I played Modern Warfare 2 and Black Ops longer. I just can't remember my playtime for both games.

Pokemon, hands down. I think Black and White had 400+ hours. And I've have all generations (yes, that means I'm quite old.)

I'm not sure, but if I had to say, it would likely be a pokemon. : X I used to spend so much time training, breeding, and battling pokemon on those games...

Team Fortress 2 - 1825 hours.

Since i don't really like to play online, my max amount of time on a game is probably no more than 150 hours.

To my knowledge it'd have to be between
marvel vs capcom 2, putting together all the arcade, dreamcast, ps2 and ps3 time.
& Warhawk on ps3 which im sure is over 500 hours

Pokemon Diamond - Over 1000 hours... and no I didnt sit there for hours breeding =P
In the first week of Pokemon Black's release I put 81 hours into it. MH4U did decently too, think it was 50ish hours in the first week. If it hadnt been for other commitments it would have been much higher.

250+ hours into Phantasy Star Online . Prob over 300 if I include both the Dreamcast and Xbox iterations.

Prob 250+ each for Virtua Tennis and Virtua Tennis 2.

Prob 70+ into the original Homeworld. Playing the remaster right now and its making me all sentimental :)

Over 100 days over 3 years on mw2.