First off, upgrading the 10-22 is a long time coming. That thing SUCKS, well at least when compared to other offerings. Namely - the Tokina 11-16 f/2.8 and the Sigma 12-24mm f/4.5-5.6 DG EX HSM.
The Tokina is the fastest and sharpest lens in the class and the only one that offers f/2.8 to all 3 formats including the widest one at that aperature for crop. Its usable on APS-H (from 12.5~13mm) and FF (from 14mm).
The Sigma will reintroduce you to UWA. Once you use the Sigma @ 12mm on FF, you will learn that the term ULTRA Wide Angle should be reserved for this lens alone... either that or it needs a new class distinction, because this lens stands alone. The Canon EF-S 10-22 was great when it was out there by itself, but times have changed and the market is full of options for UWA shooters. If you simply wish to replace the focal lengths of your 10-22 on FF, i.e. retain the same FOV's... get the Canon EF 16-35mm f/2.8L - its an awesome lens, but its expensive, and it doesn't go nearly as wide as the Sigma 12-24.