We shoot with Canon 1ds mkIII's if they're hot. If they're less hot or we're just feeling lazy then it's a 5d MkII day - The assistants now use mk II or mk III as a question, meaning is she hot or not!
I've tried other cameras, but stick with Canon for a couple of reasons. Firstly I have a lot of lenses already, so duplicating the lot in Nikon would be a PITA. Secondly, I like the look of Canon images - the colours are warmer and just more flattering - if not 100% realistic, but hey, if surfers want realistic there's always the wife.
70-200 2.8 IS is a great lens but it's also big, heavy and expensive, the 70-200 f4 IS is half the price, half the weight and in real life f2.8 hardly ever gets used so is no great loss. At f8 - f16 you simply won't see a difference in the shots. The 24-105 f4 IS is what I use 99% of the time indoors anyway, the 70-200 is just too long in a bedroom.
Don't skimp on lenses! L series are sharper, more contrasty and give better saturation plus they focus a lot faster.