According to their website HTPC TVs get you only local channel access.
Even without their equipment fees, I am still paying more than I currently am with DirecTV and this is with the first year rebates. After the first year it will go up even more.
Without a cablecard that would be true. Same with the Tivos. Using cablecards, Tivos and HTPCs function as STBs. Hauppauge and Silicon Dust have 2 and 3 tuner add-ons. Ceton has both a USB and X1 cablecard adapters for 4 tuners. Premium channel content is usually locked and can't be shared. The multichannel cablecard adapters are relatively new hardware.