People forget that the best soccer players could play as late as 39-40 years old! Beckham is only 31.
I agree. He still has a lot of good soccer in him.
I also think he will also do a lot for the sport in the US. As much as we make fun of soccer I heard that it is the most popular sport for American kids until they reach their early teens and start branching out into the other popular sports where they see their heroes making the big bucks. His popularity might keep more of the talent in soccer and elevate the sport here. That said, I think MLS needs to keep the "injury overacting" out of the US game. I think that is one of the biggest obstacles soccer faces with American mass acceptance.