GTV, at least, seems to have a credible plan for spreading to new devices. LG and Sony are pushing out TVs with embedded GTV support, and the converter boxes, which used to be pricey, have gotten cheaper.

Much like AppleTV is/was a "hobby" for Apple, I see GTV as the same thing for Google. Give them a few years and it will get more serious.

What I'm surprised we haven't seen yet is any integration of GTV (or Boxee or whatever else) into a consumer home theater receiver. Those things have increasingly complex UI requirements, for which it would make sense to have GTV as a front-end rather than the traditional homebrew kludges. Also, I suspect there's a significant overlap between the crowd who says "I want decent audio, so I bought speakers and an amp" and the crowd who might be willing to deal with the quirkiness of GTV.