Please do not buy an xti you will spend alot of time in aperture/photoshop with your photos if you buy that camera if your gonna go canon get an eos 30D or greater if not buy a nikon D40 or greater the d40 is far less expensive then the xti and i find the quality equal or greater then in most cases.
1) Spelling + Grammar - Makes the world a better place.
2) How will getting an XTi leave you in front of an editing program more so than a 30D? The 400D has a newer sensor and a larger resolution. I don't see how these would make you want to edit your photos. The D40 is only equal or greater in some retrospect. It is a tad lacklustre in features, but the audience it aims for won't usually strive for these features in an entry level DSLR anyway. e.g. DOF button, Exposure Bracketing.