There is a relatively-recent (couple of months back) driver update being offered by Windows Update, and which Canon has on its web site as well.
The update from Windows Update has refused to install a couple of times, so this evening I grabbed the driver from Canon directly and loaded it.
That was a HUGE mistake.
It instantly destroyed my color profile pass-through capability, and what's worse is that thinking it had damaged my ICC paper profile somehow (or was just biased differently internally) I re-ran that with Color Munki. That made it MUCH worse.
Apparently the "leave me alone, the app is going to do color" passthrough setting (ICC Application, Manual, no adjustments and NONE for matching) is broken, ignored, or somehow pooched in the new driver.
Whatever it is it utterly destroyed any resemblance of color fidelity and I could not get it back. Now if you happen to like a SEVERE magenta tint in everything I guess it's ok, but..... 
Fortunately I have system restore turned on and was able to roll that one back. I say FORTUNATELY because otherwise I hope you have the **DISK**, as Canon no longer has the older driver on their web site!
Just a warning to you folks who may own one of these.... don't update that driver!
Windows 7/x64 here.
