Chuck, the main reason I can see for keeping a crop body IS the crop factor. The 70-200 might be too long on the 7D for some venues but in my own church where I often shoot weddings it works out well having the 70-200 on the crop body since I can frame much tighter. Once you go above the 200mm range you're either looking at primes in the f/2.8 to f/4 range or a zoom that only goes to f/5.6. There are exceptions but they're big and heavy and don't seem to be very popular. You can get close to the 1.6 crop factor with a 1.4 TC but I think most would agree using a crop body is better than using a full frame with a TC due to the slower AF and loss in quality. If you find that you don't need anything longer than 200mm on your full frame then totally go for the 5D mark III or whatever other full frame camera they announce next but otherwise as others have said the 7D just has it's limitations just like 5D mark II has more limitations than the mark III. This is just my personal observations. I'm in no way a true professional yet but I think I'll always have a crop body at least as a backup for this reason.