If you have updated to the latest version of Google Hangout, you will notice that there is a call option now. And yes it actually works for Canadians (for now). The call quality is superb, and it essentially uses Google Voice technology without all the extra options that you get with Google Voice. Its a start for us Canadians who have been deprived and have not had a chance to legally obtain Google Voice account.
If you are a Canadian, grab the 1.3.0 version and don’t update it. I assume they will disable this for Canadians in the next update. Enjoy free phone calls to Canada and United States.