We've seen the Dell DisplayPort powered 30-inch display, and unless you see that the cable used to connect it to the PC is not DVI or HDMI, you couldn't tell the difference.
Just to please you, we took a picture of this nice and expensive device, but don’t expect too much. Our sources also indicated that it is available now, but at the same time we believe that currently you don’t gain anything with DisplayPort on this particular model. Compared to the older 30-inch model the new one has 8ms response time; but most people won't notice that.
A few months ago we wrote that Dell plans to move most of its new notebooks to using only DisplayPort, so this might be one of the first displays to support them. We are sure that Dell will launch more models in the weeks and months to come.