I know it sounds self explanitory,but what are the benifits of having this type of rear end?  How does it affect the rest of the drivetrain?  

I know nothing about this, but here's what a quick search of the web turned up:

Standard or reverse rotation front ring & pinion. This can be determined by whether the pinion enters above or below the axle housing centerline. Reverse rotation gears have the pinion shaft entering above the axle centerline and standard rotation gears enter the housing below the axle centerline.  

The term reverse rotation is a little misleading. It has to do with the cut on the ring-and-pinion gear teeth. Most refer to it as a high-pinion. On a high-pinion axle the pinion gear comes in above the axle centerline. On a low pinion axle the pinion comes in below the axle center line. High-pinion axles are srtonger than low pinion axles in a front end application because the gear teeth are cut the opposite direction. On the high-pinion axle power is transmited through the drive (stronger) side of the gear teeth. However, when a high-pinion axle is used in the rear, power is transmitted through the coast (weaker) side of the gear teeth.