It depends on the game really. I probably would prefer FPS over TPS. When it comes to shooters, I liked to be the player, not play a character.
If it were a game other than a shooter, than I would have to go with Third Person, I feel more comfortable playing in a third person view when it comes to non-shooter games.
Favorite FPS game: Battlefield 3
Favorite TPS game: Gears of War 3