Garnett's comment during the discussion of Shadows of the Damned, regarding 3rd person and lack of peripheral, reminded me of something I wanted to post during the Dead Space discussions.
I really don't see why games need to be either First or Third person. Driving games offer multiple camera options and let the player use the one they prefer, yet I can't think of many (or any at the moment) shooters or adventure games that allowed you to choose which you'd prefer. There are instances where, as in Halo, if you're in a vehicle or using a specific weapon, the game automatically switches you. It seems to come down to a 'style' choice on some games, yet if you prefer one view to the other, can diminish your enjoyment of the game.
This is one of my 3 main gripes about controls/options on games. Hell, it doesn't even have to be on-the-fly switching, it could be an option you can only change from the main menu.