With current dual link DVI we are limited to 2560x1600 resolution and once DisplayPort comes into play it will be possible to make even higher resolutions.
There is a good possibility that we will see even bigger monitors, and sizes of 30 inches at 2560x1600 and 3000+ resolutions might become a reality.
We won’t question who actually uses and needs these resolutions, but the key point is that it will be possible. Very few people that I know even have 1920x1200 displays, not to mention even higher resolutions.
Dell has decided to go down the display port road, and the connector looks good and should work quite well.