How does PSVita's 3g work?

Sorry for the wrong board, but there is no other console/psvita board on here.

Alright so i was going to get the psvita in the future, the bundle that comes with the vita that's 3g, it says it has service from tmobile i believe. Do i have to goto Tmobile and pay for it, pay extra monthly for it, or is it always activated into my psvita? Please explain i never figured this out, i believe ipads are the same do i have to like set it up and crap or does it come with the service forever?

3G only works on the Vita tied to ATNT as far as I know. It's grossly overpriced for the absolutely terrible service it offers. Just skip it entirely.

@Blabadon: Damn that's lame. Alright screw it then lol.