Early reports that I have read indicated that the 20D does not have the same sensor as the 350D and that the 350D sensor is in fact only 8mP, whereas the 20D is 8.2mP (no real size difference there). The performance seems to be close if not the same, given the choice I would take the 350D with a quality lens for the same price as the 20D with a budget lens. The 20D has better burst frame rates and is built quite a bit more solidly. (the 350D was non existent when I bought my 20D) If you have the money the 20DA factory modded for astro use is a good option as it will still take daylight pics without additional filters, whereas hutech modified 20D/350D/5D need a screw on filter to correct colour balance for daytime use.
