Argh... I can't edit my post. I forgot a big part. Pirlo is also one of the most technically gifted players in the world. This is the guy who makes the Italian National Team change entirely when he steps foot on the field. They would be playing horribly, until he gets out there. His skill set is bar above the rest. He also holds possession extremely well, and rarely loses the ball. Last season (2009-10), his pass completion rate was nearly 90%. He dictates midfield play... and it's hard to underestimate his overall contribution to Milan and Italy.
I agree here. I'd even add Marco Etcheverry in there. Sure, he never played for a team like Milan or Real Madrid, but he's won a championship in just about every team he was in (like four different countries) during his professional career. Beckham is really good, but the dude isn't great. Compared to the players above, Beckham really doesn't bend the ball as good.