Arteveld: I could never get immersed in TPP, the camera is usually wonky [or, to be more specific, doesn't work the way i'd like it to work], the character is blocking my view, and i don't really feel bad when he dies [i even took sick pleasure in dying in Tomb Raider]. I'm playing as the camera following the guy, i don't care for the view obstructing guy.
There's a number of stealth game series out there that let you play in third-person: Splinter Cell, Hitman and Thief, just to name a few. I totally agree that first-person helps you get more immersed, but when you think of it, games like Hitman or Splinter Cell are much better the way they are now, forcing you to play from a third person perspective. Not only do you get a better view of your surroundings (sure, being able to see what's around the corner without peeking isn't too realistic, but still), but you also get to see the main character as he's interacting with the environment, for example, shimmying on a ledge or climbing up a structure.
After all, it lets the developers throw a load of cool moves into the game! Nothing beats seeing Agent 47 stick a knife in an unsuspecting guy's ne... okay, well you get the picture.
Arteveld: Anyhow, i'd be happy if they made it switchable, if both ways would work as intended, it'd please the TPP and FPP crowd.
Granted I didn't mind being unable to go third-person in "Thief: The Dark Project", I'm pretty sure we'll have both options.
By the way, reading your post I remembered playing Tomb Raider: Underworld on my cousin's Xbox. The deaths really were laughable! Especially followed along with Lara's moaning.