The Xsi is a great camera, and a nice way to enter the DSLR world.

The price on it is great, and just keep one thing in mind when you go to the DSLR level, put your money in to the lenses, not the bodies...

You are going to have a blast with this type of camera, the Live View is great if you are used to looking at the LCD to frame your shots, and the custom modes (M, Av, Tv) will keep you busy for months...

I say go for it, unless you need HD Video, then I would look at the T1i, which does very smooth 720p video and somewhat choppy 1080p (at 20fps, which is strange).

Good luck, and if you ever have any questions, shoot me an email and I'd love to help.