I picked up a canon 16-35mm f/2.8 L II today. I’ve had a 17-40mm L for a while now and it’s a fantastic lens. There are 2 reasons for the 16-35 though; it’s one stop faster, and it’s 1mm wider. That doesn’t seem like much, but I’ve noticed I’ve been shooting the fisheye a lot inside when I shouldn’t simply because it’s a f/2.8 lens. Also I love wide angles, and 1mm is actually a huge difference in wide angles, so that’s helpful as well. It is a big bigger and significantly heavier though. We’ll see how they fair over the weekend and whether they’re keepers or not.