Hey Grant,

Are you lifted?

Even if you're not, I still don't think it's a really big deal.

I'll try to make this short. For all intents and purposes, there are three bars attached to the frame that hold your rear axle in place. Two run parallel to the tires, one on either side, and they keep the axle in place front to back. There is one bar, I think it's called the Panhard rod?, that runs parallel to the axle, and it keeps the axle from moving side to side.
Without crawling under there, I don't remember if it's adjustable or not. It looks like yours is a little short. Mine was the same way after I bent it offroad, the axle was misaligned, and the driveshaft vibrated like crazy. You can find a lot of posts on 'vibration while coasting' and things like that.
If you're not experiencing any noise or handling problems, I would just leave it. If you want to replace it, which is really easy (2 bolts), I think the dealer quoted me about $340. Better to get it from someone parting out here on the board.

Hope this helps.

Brian