To give you a different opinion, I personally avoid rear projection whenever possible! Rear projection screen are not as bright as front projections and typically have drastic cones of vision so make sure you understand the specs of the screen you're getting.
When you do rear projection, you also need to pay attention to where you place the projector in relationship to your audience because the light source will be visible as a hot spot on the screen.
Also keep in mind that in the wrap around setup, you'll be dealing with different focal planes so ideally you'd want three projectors to pull this off beautifully.
drazkers wrote:You're going to find the limits of your angle if rear projecting from a single projector with the second picture.
I truly doubt one could hit every part of that screen with one projector from the rear.