Ya it's working but only in US and Canada. I am waiting to start in most over the countries. I have noticed also that in the tradition Gmail we are getting facility for video and voice calls without login our GTalk messenger means in the traditional gmail. When it would be start in other countries as I m eagerly waiting for that.
I saw it too.. but I haven't really tried it.. same here.. I am waiting for it to globalized.. that would be fantastic.. lets just hope it would come sooner..
You can use it outside US/Canada to make calls there by using Ultrasurf or Hotspot Shield. If you need detailed information on that, let me know. I'll post the details here.