So, I was selected for the in-home streaming beta and just wanted to share some of my first impressions. So far It's looking very promising, but there are still some kinks to work out. This is running off a core i7 4770k, 12GB RAM, AMD Radeon HD 5850 host machine to a i5-470UM, 4GB RAM, integrated graphics laptop.
This was my first attempt, streaming over WiFi. The game is actually being rendered at 1080p on the host machine, then the video is being resized to 720p for the client machine.
There's about 200ms of latency, which is noticeable, but would still be playable for games that don't require fast reflexes. I noticed delays where the image would occasionally freeze for a fraction of a second.
Second attempt with a gigabit ethernet connection. Much lower latency, during the loading screen the video was actually at 60fps, so the lower framerate during gameplay is probably just because my 5850 can't render any faster.
Just to see if it had any effect on rendering the video, I tried to switch from the integrated intel graphics to the AMD 5450M in my laptop, but it didn't make any difference in display latency. Overall, the game was very playable over wired ethernet and you almost forget you are streaming after a few minutes. I could probably lower the latency even more by lowering the resolution and graphics on the host machine, but I haven't had time to try that out yet.
Some bugs I noticed so far were distorted audio on my first attempt. Re-launching the game seemed to fix the problem. Later on while streaming the audio volume also randomly dropped down to being barely audible. Also, after exiting the game it seems like controller input is no longer being sent. I couldn't close uplay with the controller after exiting the game, I had to use the mouse. They'll probably work out the kinks eventually, but so far it's a really nice feature. One of the nice perks is also that you can actually log into Steam with the same account on two computers simultaneously without being kicked off one of them.