I just bought the 17MM TS-E and the 24MM TS-E for my architectural shooting. I normally shoot Nikon's D600 and D4, but they do not offer equivalent lenses. So I decided for my architectural shooting to move over to the dark side.
I visited the National Cathedral for some interior shots. Getting used to the controls on the Canon is a little challenging, Nikon has more hard switches and fewer sub-menus, but I'll figure it out quickly, I've owned the 5D and 1Ds Mk III before.
First thing to mention is that Canon's knobs on the TS-E lenses are bigger and easier to access than Nikon's munchkin knobs. There is also a lock on the tilt position so I can't accidentally move it, screwing up an otherwise good shot. I did that several times with the 24MM PC-E. These two lenses also have the advantage of full rotation in any tilt movement, another BIG bonus.
There are two views of the pulpit, one shot with the 17, one with the 24, just to show the perspective differential. So far I like what I see, the color rendering is just fine, I'm seeing no barrel distortion in the 17, and resolution is holding well in almost full shift position.