Power efficiency, your cpu draws around 65 watts full load. Which isn't much, so yeah.
And yes, 8gb is really unnecessary, because you probably won't go over 2gb doing whatever. I know for a fact you really won't be using this for gaming, obviously, so that's why I said to get less ram. And 1066 is very slow compared to 1600, it's worth it, and as I said earlier, the 4gb has a latency of 9 along with the 1600, so really if I were you, I would be getting the 4gb.
just so you are aware, you cannot use a PC as an extender for WMC. You might be able to access some recorded TV but you will not be able to watch any protected content or access the tuner/watch TV or use any media center functions. The only extender for WMC is the xbox 360.
You could assign a tuner to it, but not share protected content
I was hoping there wouldn't be that confusion. I plan to assign a tuner to it, but I don't expect much more else than Web surfing and streaming from the media server. This setup should be able to handle it's own instance of WMC from the HDHomerun Prime, right?