The idea behind this test was to compare the 17-55DX and 24-85G lenses at 35 mm. The shots on the left side were all taken with the 17-55DX. They can be compared to the shots on the right side, all taken with the 24-85G at the same aperture.

The difference seems to be that the 17-55 is clearly sharper at the wider apertures and gives better contrast throughout the aperture range.
Diffraction seems to set in around F8/F11 on both lenses, causing them to loose sharpness and the differences get smaller.