has many HD camera options among its models, so you don't need to be on the networks to consider HD.
At the same time, this New York Times article on the spread of HD broadcasts notes that your local TV station may be way ahead of the networks, so it pays to ask about the technology being used if you're appearing on TV or your talk's being recorded. (As with media interviews, the camera operator is the best person to ask.)
You'll also find useful these tips on how to look good in HD, which include background information on assessing how the time of day affects your appearance, using available natural light and how to change your makeup for HD's sharper eye. (In general, it's best to aim for a more natural, rather than an overly made-up look.) Finally, remember: Regardless of the technology, few of us think we look great on video. Don't make that part of the lens you're using when assessing your video record.