Well for me there are several issues, all mentionned....
1- My ignorance: I admit I don't know much about the benefits of your product vs. plugging my current laptop or any other computer in my HT.
2- Price: Do I feel better with 1500$ in my pockets, or a HTPC?... The price seems a bit high when I (and most people in this hobby...) already have a good computer, DVD player, DVR. That's a very expensive proposition for a component that seems to offer nothing new, really.
3- Integration: I hate computer glitches, bugs, software problems, etc, etc. It absolutely kills my day. I want nothing to do with it, especially when I'm relaxing with my toys (HT)....
4- Noise: I'd be concerned about that too since I'm already using a front projector.
Don't get me wrong, the concept is really great, but I prefer to wait and see. I want to see the real benefits of HTPC versus whats already in my HT.