I don't use Canon gear but the way canon has demoted their XXD line and rapidly iterated their XXXD cameras while sharing mostly the same sensors seems to mean you have 2 logical choices. One of the XXXD cameras, something like the 500D or 550D (don't know differences but I hear the 600D is no different to the 550D so is not worth the price premium) and you get the sensor in a nice light small body saving a load of money to buy L lenses. Or you go for the 7D and get a proper camera with good handling, ergonomics, speed, AF, mag-alloy body. The XXD line now just doesn't make any sense. I used a freinds 40D a lot and it was a very nice camera, the new 60D is just not in the same league. The 7D is very nice though.
Interestingly Nikon went the other way and have progressively made each camera in the line bigger, better built, better features and moved each camera up a line. You can now drop a line of cameras to still get the features and specs you want.