After ditching comcast cable, i still use the 75ohm coaxial cable to watch the local digital and a few analog channels. All of the digital channels and the available ones were retrieved just fine by Windows Media Center - this includes the two or three digital 'versions' - ie, KTVU/Fox channel 2 for the analog, 2.1 for the digital version. KQED/PBS shows 9, 9.1, 9.2, 9.3.. etc...
with MC, I first attempted to scan for digital channels on the same tuner card, the status showed a slow scan through 68 channels, but nothing returned. i then attempted to scan for analog channels, and i got the thirteen analog (whole number) channels.
when assigning the guide and using the "digital terrestrial" version, it did not assign channel names to even the 13- i had to manually select each one and pick from the long list of 68 that were there.
the guide GUI looks good in MC17 - but the scanning/guide functionality is not working