I voted for TPS because I've found in general most of the third-person games (not always shooters) are better quality. A lot of the FPS games I've been playing recently are just generic shooters that are practically copy-pastes of games like CS with some different graphics and names.
Lots of people say they feel more "connected" to the character when it's a first person game. I feel the other way, since when you're in a FPS you don't even know what your character looks like for most of the game, and often enough they'll say about jack-shit which makes it even harder to connect with them. Plus you don't see yourself DOING anything, you usally point your gun at something and some text appears saying you're doing X. The characterization/personality of your character is just that he's some generic-super soldier who kills people. Yeah, that's easy to identify with. Oh, and have you noticed you can't see your own legs when you look down?
Third person games (MGS4 is a great example of this) you see your character going everywhere/doing everything. Also you get a lot better understanding/appreciation for the environment and maps you're playing in.
Though I do admit when it comes to online I prefer FPS since it's pretty much easier than TPS. Though I wish another good game like Battlefront would come out where you had the option of either.
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