Here is my review on the 11-16.
http://e90post.com/forums/showthread.php?t=176012
After having used it for a while now, i have noticed that the Tokina is no where near as sharp as the canon 10-22. Maybe i just got a bad copy or something, but at 100 crop, its noticeably less sharp then the 10-22. I still think the lens is great "bang for buck" and having a faster lens is truly helpful when shooting at night. But if i had to pick one or the other, im not so confident i'd pick the 11-16 again.