Well yes and no. Today's standard computer monitors can handle the resolution of HDTV without a problem. By the way, some computer video cards are designed so that they can use an HDTV instead of a computer monitor if a person wanted to do that.
This is kind of ironic, everyone in the entertainment industry have been harping for more clearer television and when they get it that, they get a little more than they asked for.
You're probably thinking of the DVI interface - most HDTV monitors already have a standard 15-pin VGA port attached, letting you use it as a computer monitor with any ordinary graphics card. But, of course, that's an analog link, versus the DVI port, which is digital all the way through...