I know TV is not quite within the scope of computer advice, but I’ll branch out a bit with this short article. (I promise not to let it happen too often!)
Feb. 17th is the start of HDTV only broadcasts in the US. Check out https://www.dtv2009.gov/ for details.
If you’re planning on sticking with or even switching back to an antenna, here is a useful site that will help you pick the right one. http://www.antennaweb.org/aw/welcome.aspx
Want more information on HDTV vs SDTV? Check out Wikipedia’s page on HDTV.