ok, I've tried the game streaming.
it's an interesting feature. for me it did a few things:
1) reinforced the idea that my wireless router may have issues. worked tolerably well on my 5 GHz net, not so good on the 2.4 GHz. trouble is the range of the 2.4 is less than half that of the 2.4. I encountered a lot of network trouble. for the time I'm assuming it's my aged infra and not the unit. streaming 720p apparently can be network intensive. my 5 GHz network has nothing on it. that's mostly because of the range issues. it does make for a low traffic and high throughput network. however, I do have to wonder how much of my throughput issues were caused by a 5 year old dual band router and how much was caused by having the shield as a bandwidth hungry device on a 2.4 GHz network that supports about 6 clients (on average).
2) it reminded me of why I like to play a lot of these games with a keyboard and mouse rather than a gamepad. I like keyboard and mouse. felt superior when driving cars in saints row III, but that's about it. shooting people was just blah...but I never play these games with a gamepad.
3) it streams more than just the "supported" list of games. I can stream anything from my steam account. I had thief running at one point but I couldn't conveniently control it (I could do WASD via virtual keyboard and mouse via touch screen, but that's no way to play a game). ftl launched and gave me a menu but I didn't bother starting a game because I doubted I'd enjoy it. amusingly enough fez is listed as supported but that just didn't work (blank screen). at one point I saw my desktop which makes me wonder what mechanism is built into the nvidia 6xx series of card that lets them do this streaming. is it some kind of terminal server?
I need to play with it a little more. I guess some device has to do it first, but I do have to question the wisdom of trying to sell an expensive device that has such an expensive and specific set of requirements (nvidia 6xx card or greater, really reliable 802.11n network).