A part of me thinks that the cpu/chipset are going to be obsoleted very quickly with next gen AMD/Intel solutions around the corner (like Sandy Bridge).
This thing needs to be marketed to general public, not geeks who come here
People on internet forums can usually build their own and will always have that as a comparison point. Most people don't care about the parts, they just want it to work well.
So the price is not the most important concern as long as its not a shocker. I think there a HTPC can me marketed to the general public. Package it well, add all the correct drivers, and put something like the free XBMC on it, or MediaBrowser. Partner with them.
Put it on store shelves next to the big screen tv's with amazing demos. Boxee box is trying to do exactly this but this is a complete pc that families can use for many different things, and enjoy all their media.
Maybe this is the wrong direction but I sure would like to see a product like this.