On a hunch, I decided to scan available GSM operators from my N900 this morning in Toronto. Wouldn't you know it, 'CAN 490' was displayed showing a nice little '3G' symbol beside it !
But alas, when attempting to connect, I was denied.
Some Googling of CAN 490 revealed that it is indeed Windmobile (Globalalive Wireless).
Come on Canada - we need choice now! Let Windmobile throw the switch.