Google Voice now in Canada

When I came back to my desktop earlier today I was surprised to see something new in my Google mail.  A feature that will allow one to call any number in Canada or the U.S. from their desktop for free (at least for 2010). 

Now, I was working and didn't have a lot of time for exploring this, but I did make some calls (only one that was completely unnecessay) .  It seems to work just fine.  I look forward to exploring this new Google feature further.  Have you had a chance to look at it?  Do you think this is a 'Skype' killer?

Comment below and let me know what you think.