From the folks at icanhascheezburger.com. This PSA is at least as effective as NAB's. Also, less likely to be forgotten:

A coalition of groups filed comments with the FCC in support of the mandating of Digital Television converter box specifications that would open up unused TV bands to unlicensed devices. Without these mandates, manufacturers will refuse to spend the extra few cents it would take (per several hundred dollar device) to filter out of band emissions. Thus severely limiting the reuse of unused frequencies.

As the press release states:

For close to a generation, telecom policy analysts have argued that the TV broadcast band was extremely inefficiently utilized and that parts of it should be reallocated for more efficient uses...the quality of the converter boxes NTIA mandates will affect the utility of the white spaces within TV channels 2-51. The stakes in enabling use of TV band white spaces by unlicensed devices are critical. The desirable propagation characteristics of TV band spectrum make the white spaces ideal for the deployment of high-quality, affordable fixed and mobile wireless broadband services, particularly in rural areas where such services are vitally needed and where the most TV band white space exists. Fostering the deployment of affordable and ubiquitous wireless broadband services will allow more households and businesses to access the Internet, and will carry enormous benefits for small business productivity, as well as for government efficiency, public safety, and education. Opening up more unlicensed spectrum will provide a new hotbed for innovation in wireless services.

You can read about the importance of this little-followed rule-making here, or download the coalition's comments here.