After all 7 moves Pfren presented in that game (which happen to meet all Stockfish's first 7 preferred moves), Stockfish say white is ahead +0.56 pawns, which in my opinion is not negligible in high-level chess (is it?).
Also, Fritz 15 said this is what white wants to play (i.e. accepting the sacrifice but not trying to defend that pawn at any cost):
Wojtaszek was well prepared (as expected), played "state of art" in the opening and got a small advantage- which actually can happen with ANY normal opening. He was positionally outplayed in the middlegame.
Do you really think that GM's care about a Stockfish +0.56 at move seven? I can assure you they don't, simply because such an early evaluation cannot be serious.
@richie_and_oprah : wrong, as pfren just pointed out.
Jobava and Rapport play it on a regular basis, Mamedyarov plays it sometimes, like Ivantchuk, etc...
And not against weak players, they can play and win against players like Kramnik...