yeah, it would be checkmate. if Qxf2, the white king couldn't take the queen because you can't move into check, regardless of if the piece that would be doing the checking is pinned (because you can't take the king anyway).
if the way i explained that makes any sense.

Hi!
http://www.chess.com/livechess/game.html?id=328513339
In this game black play. If 17..Qxf2 checkmate? I have the doubt because the rook in f7 is pin. So if black make the move the whit king can take the black queen? I think no bud im not sure.
Can somebody help me?
Thanks