Though I have no doubt that the 85 is sharper, but I decided to go for the 17-40L because I shoot my kids indoors allot and I don't have allot of room. An 85mm on my 1.6x crop is too tight. (thought it's second on my list after one of the 70-200) Even with my 50mm 1.4, I need to use my 550EX flash indoors allot because I have the 10D which is not as good at the higher ISO values like the newer bodies.
Of all my limited lens that I have, I actually have my 17-40L on by default. Thought I shoot with my 50mm for portraits, I found that sometimes (in my limited space) I find my self switching to the 17-40L. For example, here is a shot at 22mm.
[IMAGE TOO SMALL, NOT RENDERED INLINE]
You may or may not relate the indoor crampness but this is just my two cents. I think both of these lens are pretty easy to get good shots from just like everyone said, depends on where and how you use it. I actually got this lens to do landscape but found it to be useful just about everywhere else as well. Plus, it's a real tank of a lens being an L series. Sorry I didn't man to go on, probalby should have stopped at, "ya, the 85 is sharper".