I would have to say that Albert Pujols is the best player I have ever seen in person. You can call me a homer, but I would say that if he played for the Cubs. And I've seen some people like A-Rod, McGwire, Ozzie, Nolan Ryan, Ichiro, Palmeiro, Clark in the Big Leagues, Strawberry, Edgar Martinez, and etc.
Pujols is the first guy in Big League history to have at least 30 home runs, 100 RBI's, and hit .300 in his first eight seasons, and he's only 13 RBI's away from his ninth. The record for seasons like that is 12 held by some guy name Babe Ruth. And he didn't start his career like that- OK, he was pitcher, but still he hit 29 in 1919, his last year with the Red Sox.
He is also 29, and he has 351 home runs. He's on pace hit 400 by the time he is 30, which is over halfway to Barry Bonds, and 500 by the time he is 32, and could conceivably have 700 by the time he is 36 if he can stay at this pace.
To me, what makes him so great is the fact that yes, he's a tremendous offensive force, but he's also a Gold Glove caliber first baseman, and he's also becoming a very good baserunner, even though he is not all that fast. He has 10 stolen bases at this time.
I saw him playing against the Braves in Atlanta a couple of years ago, and he essentially won the game for the Cardinals. There aren't very many Big Leaguers you can say that about.
I do agree that it's a little bit premature to annoint him as the greatest, but as long as he stays healthy, he has a really legit shot at it. I just hope he doesn't get caught using steroids or something like that.