EDIT: You should realize that most TV broadcasters are currently broadcasting on two separate frequencies, one for analog and one for digital. The full power broadcasters are required to cease their analog transmissions after 2/17/2009. Many will "move" their current digital channel (although the logical channel number will remain the same). Digital (ATSC) TV uses the same spectrum that has been used by analog TV, however as part of the switch over, current channels 52 to 69 will be returned to the government and will become the "700 MHz band".
Here is a list of the over-the-air TV frequency usage:
054.000 - 072.000 TV Channels 2-4
076.000 - 088.000 TV Channels 5-6
174.000 - 216.000 TV Channels 7-13
470.000 - 506.000 TV Channels 14-19
506.000 - 698.000 TV Channels 20-51
698.000 - 806.000 TV Current channels 52-69