My response is in line with many others: CableCard, DirecTVCard, DishCard are all REQUIRED add-on functions for any of the HTPC products out there. Since those products don't exist, to my knowledge, as of yet, then why have a $1,500+ HTPC in my rack? So I can watch downloads? Or play video games? Or watch a DVD? Really, for that much money, there is better equipment already available that tends to be superior in almost every aspect at doing those jobs.
What is a HTPC good for? How about DVD ripping... oh wait, that's illegal!
Music server? Well, a 60GB iPod tends to do that for a grand or more less!
Control of your gear? Maybe... if properly implemented, that would be a perk.
I think it will all go to HTPCs down the road, but really, right now? Not even close! We are still dealing with HTPCs that seem barely better than those offerred 10+ years ago! Windows 95 machines with DVD players and a hard drive. What has changed that allows me to finally view ALL my television shows and time shift them appropriately, etc.? Yes, my PC is now 30 times more powerful - but really does little more.