First off the N1 and the G1 are different phones. The G1 was the first android phone.
I don't know what their Vancouver plans are like but the Wind AWS version will also theoretically work on the Mobilicity and Shaw networks.
In terms of plans for the Big 3, you should call or visit a store and talk to a Rep. Keep in mind though that they will be eager to sell you a contract, and if you get a version of any phone for the Big 3 it will never work on any of the newcomers