I didn't mention "sharpness" because there isn't much to say. The camera is from the same image quality mold as the 10D and 1Ds, and Rebel for that matter. The imaging chip may have slightly different pixel pitch and size, but otherwise they are of the same design, though as I stated each generation gets a bit better.
People shouldn't look for some dramatic change in this area. The real story with this camera is the shooting performance, not the image quality - which is terrific.
At 8MP it will produce bigger prints than those from a 10D and smaller ones that those from a 1Ds. There will be small differences in noise at any particiular ISO and small differences in colour balance. Otherwise Canon's current cameras produce pretty similar image quality. The rest is pixel peeping.
Michael