A few notes. Yes, the DTVPal
DVR and the TiVo are the only
HD DVRs still marketed to the public, that record
OTA. (There is also the Moxi
HD DVR, but it only records cable, not
OTA. The TiVos record both
OTA and cable.)
Samsung, Cisco, Pace, and Motorola also make DVRs (though specifically for cable). None of them have shown any interest in marketing to the general public.
TiVo, of course, has been doing this for quite a while. They have been having a very hard time achieving two profitable quarters in a row. There just isn't enough money to be made in this space, apparently. People simply don't care to pay enough, and the costs are just too high, for sustained profitability.