I have seen several reviews in the French Press (Chasseurs d'Images) that say that the Canon 17-85 is a bad match with the latest generation of DSLR's. It is just too soft to match the resolving power of the sensors. Put it on a 18Mpix DSLR and on a 12Mpix DSLR and you don't see any difference in the amount of detail because the lens was already at its maximum at 12Mpix.Originally Posted by Kag12
It's unfortunate because it is nicely built, covers a useful range and it is cheap. But for the 7D Canon released the 15-85 which is much better - at twice the price.