I prefer 7D
Since the promotion is on it is hard to pass up. I have to upgrade my glass so it pays double savings to do so with the body too. The 40D is great but the 7d is just that much better.
Since for glass I am looking at the 17-55mm is efs f2.8 at 60 savings and the 70-300L is zoom with another $100 in savings. That means I save an additional $160 if I get the body. Since I know I'll be upgrading at some point soon it is a no brainer to do it now. Also if the firmware rumors come true it will be that much better a camera.
I am hoping with the glass and new body my keeper rate goes up. The kit 28-135 and 70-300 is lens of old just doesn't cut it anymore. Especially now that I am pushing them well beyond what they were designed to provide.