uh they're just stopping analog broadcasts over the air and switching to digital (ATSC) which this supports. of course pretty much all tv tuners support that now so i dunno why you'd want some piece of crap off some no name website when you could just pick one up at circuitcity bestbuy or newegg.
of course you could even go one better and get something
like this which supports clear QAM which means it can decode all your unencrypted digital and HD cable channels. typically the local channels wouldnt be encrypted so you wouldnt need an antenna and you could get some extra cable channels out of it. things like ESPN HD would usually be encrypted but you wouldnt be able to get those any other way anyways.