I've used usvideo.org for a few weeks now, and it seems to work for me. I updated the DNS in my router and all devices in the house use the service.
Yes, for services like Netflix where it wants to identify you as either US or Canadian, it will think you are US.
For everything I've tested, it seems to work. The only significant exception is the Cartoon Network, which is one of the sources that comes up in Boxee for content so it's somewhat annoying that it doesn't work.
Just testing for now to provide some background for my blog, haven't decided if I'm going to stick with it.