Let me start off by saying that Jeter won three gold gloves in a row from 2004-2006. Even if you say Jeter's range is diminishing as each year goes by, you are forgetting a lot of his talents that are far more important than his range to his left.
For those concerned with his fielding skills, you may have forgotten that he still has a quality arm and is a master at backhanded plays. While he may not have the greatest range to his left, he certainly makes up for it with his jump-throw play in the third base hole down pat.
Another point I want to get into about Jeter is his offensive skill set as a number two hitter. I believe a true number two hitter is a rare and valuable quantity these days. I would rank Jeter second in all of baseball, only behind Dustin Pedroia, for number two hitters. Oh by the way, any coincidence that Pedroia was MVP last season?
If you compare Pedroia's '08 campaign to Jeter's second-in-MVP finish in '06, they are strikingly similar:
Pedroia: .326/.376/.493, 118 R, 213 H, 17 HR, 83 RBI 20 SB
Jeter: .343/.417/.483, 118 R, 214 H, 14 HR, 97 RBI, 34 SB
Oddly enough, they also both won the Gold Glove and Silver Slugger awards for their respective positions. (I still say Jeter deserved the MVP in '06 far more than Joe Mauer.)
The prototypical number two hitter needs to possess all offensive skills: hit for power, steal bases and have good bat control in order to move runners over via bunt or a hit to the right side. If you are not convinced, here is more wisdom from Dave Cameron.
Anyways, Jeter's positive impact on the Yankees' four championships is undeniable. He scored at least 104 runs and batted over .314 in all four championship seasons. In the four World Series', Jeter's combined batting average is .342. He also captured the World Series MVP in 2000.