So its not the anticipated announcement from Canon about a Mk II 5D but it is an upgrade to 400D/XTi.

Pre-PMA 2008, Canon has announced a new compact digital SLR, the twelve megapixel EOS 450D (Digital Rebel XSi). On the surface a very similar camera to the EOS 400D, however there are a range of significant improvements. More information via the link below:

DP Review