On February 17, 2009, all TV stations will cease broadcasts of analog signals and go completely digital.  What this means is that analog TVs will be obsolete, so anyone with antennas or rabbit ears would no longer receive TV signals.  People with satellite and (most) with cable boxes should be unaffected.

Instead of forcing everyone in the US to buy new TVs that don’t already have digital signal capable equipment, a $40 coupon for a converter box is being offered here: http://dtv2009.com

Here is a list of converter boxes that can be purchased with the $40 coupon, but you may have to put an additional $10 or so towards it as well, since the estimate price was rumored to be somewhere around $40-$60.

On the website, it says the coupons should be on their way out in late February or sometime in March, and are only good for 90 days from the date of issue.