While DisplayPort is still in its early stages with only a few products released in late 2007, there is a lot of potential for the video connector. The real test for it will be how it is integrated beyond computer products. HDMI is heavily entrenched into the home theater market and is making progress with PC companies. Displays are not likely to really go beyond the 2560x1600 resolution or 24-bit color depth in the near future either. The other key feature will be the auxiliary channel to be used for carrying other data beyond the video signal. This is one that many notebook manufacturers might be willing to pick up on to simplify their designs and products.
To put it briefly, this cable is required for anyone who buys an ATI card supporting Eyefinity Technology and wants to run the extra (3rd) monitor that has only HDMI/DVI inputs.