500 reasons to pay attention. (Closer).

Milestones are everywhere in baseball. The biggest ones are 3,000 hits, 300 wins, 500 home runs, a .400 batting average and the Triple Crown for hitters and pitchers.

The one mark that is evolving the fastest is 500 homers. If you have 3,000 hits, you're an automatic Hall of Famer. If you reach 300 wins, you're in also. But in this era of great hitters, 500 homers may not get you an automatic berth the way it used to. This season, Sammy Sosa and Rafael Palmeiro already have hit their 500th homers, and Fred McGriff has fewer than 20 to go. After those guys, Ken Griffey Jr. is 31 homers away, a mark he's sure to reach, and Juan Gonzalez entered the week with 417. …