Want/Need New Lens

Selecting lenses is really simple. Find the voids and fill them in the order of most importance. No void = no lens.

I know that "need a new toy I don't need" feeling. Its like being hungry, you can put off satisfying it for a while but sooner or later you're gonna feed the beast.
That being said, I think the 70-200 IS: its a lot smaller and lighter than the 100-400 so it might be more convenient, probably a bit sharper, much better IS system.
Or if you want something totally different, then an MP-E 65mm 1-5X Macro and a macro light. If you go Macro, might as well go overboard

jra wrote in post #2279371
With your budget, you could get both the 100 macro and have enough left over for the 17-40. Seems like a win/win situation Not to mention, you'll get the 17-40 off your short list, that way you can add another

I agree. I have the 24-70L and I still grab my 17-40 for those shots that need to be wider. On the 5D, that's really wide! And you can get 2 lenses for your $1200. Win-Win.