As a quick note, a lot of people have apparently been booing Alex Rodriguez with his recent struggles. It's About the Money, Stupid has a good intro to the piece, and covers most of what I would say. I want to throw out some extra thoughts, though.
First, the playoffs are a small sample size. We are only talking about three games, in the Yankees' case; any player can have three bad games. Especially A-Rod, who has been hit with injuries late in the year; he played only 99 games this season, and only 19 after the break. And he still doesn't seem 100%; his post-break batting line was only .191/.345/.353. Maybe an injury-hobbled player shouldn't be batting clean-up, but that's a different point.
In any case, he hasn't been totally useless. He is still playing solid defense at third. He is 0 for 10, but he has managed some productivity (3 walks, 2 RBIs if you prefer those). He has been useful to an extent; maybe he should be batting fifth/sixth/seventh instead of fourth, but he should definitely be in the line-up.
Also, some may mention A-Rod's prior post-season struggles. Out of curiosity, I looked up some numbers (although I'm sure someone's made this point before):
Player 1: .766/1.047/.973
Player 2: .932/.756/.832
Those are their career OPS, by playoff round (Division Series/Championship Series/World Series). Player 1 is noted playoff choker Alex Rodriguez. Player 2 is noted playoff clutch-guy Derek Jeter. So no, this isn't normal for A-Rod; his injuries are limiting his game, but he is still providing the Yankees with some value.