To me the problem with another Rebel/ most of the SLR lineup is that they are redundant of each other. Why use a Rebel when there is the 5D. the Rebel's usefulness is not that it is an SLR, it's true quality comes from being a small, cheap camera capable of creating great image files and cheap enough to abuse without having to eat all those Antacids. To be honest if someone truly cares about using the viewfinder/accurate AF in a certain situation there are better options it the Canon lineup, right?!
What's not in the Canon lineup is a truly rugged camera that produces quality image files. I'm sorry but there is NO way the G-12's sensor size does this. And you have to admit there is a hugh hole in the digital camera line up from all the brands. And that is to replace the Nikonos, but to take it further and make it not only for underwater use but for times when you just don't want to abuse the 5D/7D cameras having it small enough to use in active situations. UW Housings make photography impractical in a lot of informal situations.