Bearhunter, that is an awesome camera you have there. Give the old camera to your wife, and keep the xti in your pack. (don't tell her I said that)
Just so you know, the camera is just part of the equation. You'll need to invest in some good glass. When you get ready for that, let me know. The camera can only see what it's looking through. Just like binos and spotting scopes, good lenses are most important. Even more important than the camera body.
Did you get a kit lens with it?