Bob Atkins has published a useful overview of the differences between the Canon EOS 10D and Canon EOS 300D digital SLRs, and tries to answer the question “Which one should you choose?”.

“Overall the 10D is a more professional camera, with features lacking on the digital Rebel (EOS 300D). Both use the same 6.3 megapixel size sensor, in fact they both probably use the same sensor, so assuming you use the same lens and the same exposure on both bodies, you should get images of equal quality. But of course you can say exactly the same thing about the Rebel and EOS 1v film bodies and there aren’t too many people torn for choice between those two!”

Website: Bob Atkins - Canon EOS 10D vs. Canon Digital Rebel (EOS 300D)