Body appears to be very similar to current Rebel XT (350D). Big changes are:
-- 10.1 MP sensor
-- 2.5" LCD
-- Lots of anti-dust measures (more on that below)
-- $899 with kit lens
More on the anti-dust measures:
The EOS Digital Rebel XTi employs what Canon calls the Self Cleaning Sensor Unit. The technology keeps the low pass filter in front of the camera’s sensor clean by using ultrasonic vibrations to shake dust off the surface. The vibrations are activated for one second each time the camera is turned on or off, or via a command in the menu.
The dust that shakes loose from the filter falls onto an adhesive strip that captures it, so it won’t float back onto the filter.
Just in case a speck or two remains, Canon also offers a fallback. Users can activate the Dust Delete Data function, which maps the size and place of any remaining dust. The mapping information is attached as metadata to subsequent photos. Once users transfer the photos to a computer, they can apply a dust delete function which subtracts the dust image from the photo.
Canon also applies a couple of other simple techniques to reduce the potential for dust to ruin a photo, including treating the filter with an anti-static charge to help prevent dust from sticking to it. Canon also used new materials in the body cap and shutter that are less likely to produce dust particles during use.
Looks like they put some real effort into the anti-dust measures. Nikon really should have done something like this with the D80. :(