I had a chance to try one of these on for size last week. I picked up the phone and called the manager to a local pro shop to see if I could take one for a spin - though I couldn't pull the trigger on buying it outright it was a blast to play with one. Not sure about everywhere else but these new gen TS lenses only started popping up early this year even though Canon announced them in 2009.
The difference in IQ from the TS lenses Canon released almost 20 years ago is pretty dramatic. While they never made a 17mm version before, the new 24mm tramples all over the older model. See a nice review of it here.
24mm - head to head with the older gen:
The 17mm TS-E Tilt-Shift is a serious hunk of glass. The thing exudes quality but taking care of that front element in the field might be problematic. And to think not getting your Hesalite crystal scratched was hard...
The controls are pretty tough to get to on my crop sensor 50D but still passable and I guess prolly the same on the 7D too since they both have a built-in flash in the pentaprism - and FF is really the way to go to maximize the 17mm's advantages. Maybe I'll try the new 24mm TS out next time and see how that goes. But check out the lens cap - it goes on using a bayonet mount!