Jack Bauer is brought to the console in a decent game.
The graphics aren't that great to look at although the character models are done well. A lot of of textures of the environment are pretty bland.
The sound and music is the best thing about the game as it has all the voice actors/actresses from the show who act just like they do on the show including yours truly, Kiefer Sutherland as Jack Bauer. Sean Callery who does the music for the show also lent his talent making new and familiar themes just for the game. The sound effects are the weakest part of the sound though as they sound very generic.
As far as the replayabilty of the game goes, you can go back and unlock character models that you look at (yea I know, not very exciting), but other than that unless you're really a die hard fan of 24 I can't see anyone going through the single player more than once.
Overall I would say unless you're truly a die-hard fan of 24 I would just rent it or at the very least buy it at a real cheap price. The game does well on bring the show to life, but it's still not as great as the actual show.