I recently purchased the new Canon EF II 70-200/2.8 USM IS. I now have a second, favorite lens in my bag, the first being the Canon EF 10-22/3.5-4.5. It has caused a dilemma though; do I take the 70-200 or stick with my 100-400. For now I am keeping both of them. If I am shooting specifically with a model, the 70-200 goes, if I am shooting anything else, the 100-400 goes. I love both lenses. The Canon EOS 7D is a dream body, fast and accurate, especially now that I have figured out how to control the focus points in the camera. I am contemplating stepping up to the Canon EOS 5D Mk.III, however if I do that, it also means that I would have to pick up a 16-35/2.8 to go with it. A bit more of an investment in my passion.