I have experimented with a Roku and antenna reception of digital programming at the house and have mixed success.
I am currently using an RCA ANT1450B Multi-Directional Digital Flat Amplified Home Theater Antenna. The picture quality is great as a digital broadcast should be. However, I am not getting all of the channels I expected to. The signal quality is best upstairs and worst in the basement. Of my channels of interest, I get CBS, Fox, Ion and Universal Sports. I am not getting NBC or ABC reliably which means no Law & Order or House. I also get PBS and some several odd ball channels broadcast in Spanish.
The Roku is pretty cool and the picture quality is great. I will end up paying $7.99 for Hulu plus access. House is available via Hulu Plus. Law & Order, Criminal Minds and CSI are not available.
Based on my preliminary results, I am still planning to get rid of cable and am considering getting rid of Tivo, which costs $129/year and without cable I would only be recording a couple of programs/week.