I spent about 3 months over-reasearching SLRs last summer. The XTi is a good camera, and the price on it has really come down since I was looking. However, if you can up your budget just a little bit to get the 8.0MP EOS D30, I think you'd be a lot happier. Definitely try both out before buying. And while the guys at Vistek are very knowledgeable, I've found their prices to always be quite a bit higher than at the Camera Store (
http://www.thecamerastore.com/) or even Saneal Cameras.
If you chose to go with a Nikon, take a look at their 18-200 lense for a great wide/zoom all-in-one lense.