freitasm: It does support DVB-C. At least gives me the option to search for either aerial or cable when I select my HDhomerun.
Have you actually tried to scan?
From what I've read, it will list DVB-C tuners and related options... but scanning for digital channels fails with "0 channels found".
Why else would tuner vendors have to create virtual DVB-S or DVB-T tuners to wrap their DVB-C tuners?
http://www.dvbsky.net/download/doc/WMC_DVBC_Config_Readme.pdf