http://www.pocketgamer.co.uk/r/PS+Vita/Borderlands+2/review.asp?c=59888
I knew Pocketgamer were going to give Borderlands 2 a good review. Because they're one of the only review sites who look at games from a handheld/mobile only perspective, rather than constantly comparing to PC's/home consoles.
(They gave it 9/10, for reference).