I found this one out when I called WIND to switch to their $29 Back-To-School plan, and (rather despairingly) asked if I could get a GSIII as well. Apparently, they opened up the GSIII for purchase without actually telling anyone.
You still cannot buy the phone outright. If you have a WIND phone number and a Tab, you need to upgrade on your Tab. If you have a WIND phone but no Tab, you'll need to switch to a Tab, which means changing your plan. So if you like your current plan, you may not be able to buy the GSIII yet.
Either way, you do get to keep your existing phone number.
Unfortunately, no store in Calgary has any white GSIIIs in stock. They said "a couple of weeks" for more stock. Since I don't want blue, I'm stuck again. (Irony just continues to proliferate abundantly.)
They also said outright purchases in "a couple of weeks". My impression is that the staff at that store say "a couple of weeks - hopefully" to nearly every inquiry, and they do not really know for sure. So don't hold your breath.
As I'm going to be away for about two weeks, I'll be re-looking at this mid-Sept. If their predictions are correct I'll be able to get a white GSIII outright, although I may still elect to use a Tab. If I keep it for 3 years, WIND will pay off about $150 of the phone cost, which ain't bad. If not, it's no worse than buying outright.
The irony is I would have happily bought the phone outright weeks ago.
However, if you've been anxiously waiting for the opportunity to grab a GSIII (and change your WIND plan too) now may be the time. (Or, maybe, at least time to invest in some of the accessories on eBay so they arrive before you do buy the phone.)