Kelly Johnson and Yunel Escobar are very similar hitters. Take a look at their 2008 stats:
Both guys shared time between hitting leadoff and hitting second in the batting order, but neither of these guys are really leadoff hitters -- they are both ideal hitters for the second spot. This is the key argument for why the Braves should trade one of these guys, and it seems to be the Braves preference to trade Johnson.
Escobar is under team control for longer, is arguably a better hitter, and is a defensive whiz at shortstop. Kelly is arbitration eligible, can be a streaky hitter, and is likely at the peak of his value. Yes, it should also be mentioned that Martin Prado seems ready to step in and play second base every day in the majors, while at the same time there is not an obvious or solid choice to replace Escobar at shortstop. But Prado will not be put in the same situation in the lineup that Johnson was.
The odds are that whoever starts in center field next year will hit leadoff -- be it Jordan Schafer (hopefully), Gregor Blanco, Josh Anderson, or some combination of the three. Each of these guys have speed and are good on-base guys. That leaves either Escobar or Johnson to hit second (presumably Escobar if we trade Johnson), followed by Chipper, new power hitting left-fielder, then some combination of McCann, Kotchman, and Francoeur, followed by a guy like Prado in the eighth spot in the lineup.
This is not meant to try and predict our lineup (rosterbation, I believe it was called) only to show that our lineup does not need two number-two hitters, it needs another legitamite power threat, and Johnson might be the best chip to build a trade around to acquire that power bat. I'm a fan of Kelly Johnson like many Braves fans, but I realize that our lineup needs more pop than Johnson can provide, and I prefer Escobar batting second. I sense that the Braves feel the same way, and I think there's a very small chance you'll see Kelly Johnson in a Braves uniform next season.