I heard some rumours before PMA that there was going to be a 5D upgrade at PMA. We all know how that turned out. If I remember correctly, the upgrades weren't huge, a sealed body like the pro models is the only thing I remember...

I heard an interview with a rep from Canon on a podcast, and he promised that the Mk III was going to be the only new DSLR from Canon this spring. so who knows what to expect this fall.