Canon just announced Rebel XSI 450D DSLR Camera.   This is a small 12 Megapixel DSLR.   It used a SD Memory Card.    It shoots in both JPG and RAW.   It uses both EF and EF-S lenses.   It has a 3.0 in LCD screen and can be used in livemode.  

Pros: the live view and 12 MP are great additions to this camera.   If you already have a Canon Rebel DSLR, it may be worth upgrading for the live view

Cons: I believe that it is a bad idea to use the SD card if you are upgrading.   The previous Canon DSLRs use CF memory cards.   This means that you are going to have to purchase all new cards for this camera

Overall: I used to own a Canon Rebel 300D.   I currently shoot the Canon 10D.   I am not interest in this camera and would rather pay a little more for a 40D