I generally regard expenditures of this magnitude as relatively long-term investments. For me that means if I buy it, I'd better like it for a long time.
I started with a 30D with that in mind, and the primary reason I went for the 40D relatively soon (a few months) afterwards is that the 30D is still just a tiny bit smaller for my hands than I'd like, while the 40D fits just right (there are other reasons, such as the cross-type focus points all around and the interchangeable focusing screens on the 40D, but the hand grip was the big deal for me).
A $400 difference between the XTi and the 30D may seem like a lot (when comparing brand new with brand new), but amortize that over several years, which is how long you'll have the camera if you really like it. It's not that much over that amount of time.
Also, I've found that how comfortable the camera is to hold has a big impact on the pleasure of shooting, and you might be the same. If so, you definitely want to buy the most comfortable camera you can get your hands on (at a price you can afford, of course).
All that's just my opinion, of course, so take it for what it's worth. But if the 30D is affordable to you and leaves you with a few hundred for glass, I'd go for it.
... Someone talk me out of this! haha hope the hubby does not freak out to much! 
