Canon 10-22 vs Tokina 12-24

[ItsReallyDarren]

Ive been considering a wide angle lens for a while and I now have the funds to buy one. For lenses I hear its better to stick with first party equipment because of its usability down the line as new camera bodies come out. Which is what Ive been juggling in my head for a while.

I would naturally lean towards the Canon lens but in the back of my mind I hear Canons statement of their intention of moving to full frame sensors eventually. So is it worth it to spend extra on a lens that could be unusable or obsolete a few years down the road? Assuming full frame cameras fall into the affordable level. Or since its only a $200 dollar difference and by the time full frame cameras dont cost that extra premium the money saved wouldn't have made a difference anyway.
Wheres that magic 8ball when you need it...

To sum it up, Is the Canon 10-22 worth the extra over its Tokina counterpart? For example, I could use the money to buy the battery hand grip and an extra battery.
I know the final decision will be based on what criteria I consider most important, Im just curious if the 10-22 packs that "umph" for the extra it charges.

[coldrain]

Take a look at the "interesting test results" thread I bumped up again. You can see how both lenses perform optically.

[D Thompson]

I got the 10-22 a couple of weeks ago and while I haven't had a lot of time to use it much, I like it so far. No experience with the Tokina. I bought this for an upcoming trip to New Mexico. Everything I read about the 10-22 has been great. "L" quality without the price! Check this http://www.pbase.com/cameras/canon/ef_s_10-22_35-45_usm for a lot of examples.