I hadn't thought of that. I have a older full size htpc running a x4 610e. I don't leave mine on all the time but if someone did a system like this would save them alot of power. When this board I have ordered comes in I will hook the kill a watt to it and see what kind of power it is using, although I am sure it would do better with a pico type psu than the antec 150 watt one as I don't think it is 80 plus efficient...
I have a x4 610e in a shuttle SA76G2 system paired with a HD7750 as my HTPC, this thing is drawing about 45w at idle or downloading, it's been 24x7 for over two years in my living room. Power usage is not a big deal but it's noisy sometimes, you can hear the high pitch noise from the 3.5" hard drives. I was planning to get this 1037u itx system to lower the power usage and reduce the noise using 2.5" hard drives, for video playback HD4000 of 1037u is good enough for most movies.