ok fair point but the 40d has a kit lens that is worth $1000
compard to the kits lens on the 400d that is worth $300
hence - is this already a good upgrade?
It's only a good upgrade if you want/need the lens. Don't get the kit if it's just cause the lens is a good deal.
As for the cameras from entry to top end of the cameras still listed on the Canon Digital EOS website:
-350D/Rebel XT ~$500
-400D/Rebel XTi ~$700
-30D ~$950
-40D ~$1300
-5D ~$2500
-1D mark III ~$4500
-1Ds mark III ~$8000


