Word. Big Blue's got your back.
Starting with the launch of 3.0.8, you'll be able to roll a new Death Knight on any realm as long as you have a level 55 character somewhere. The normal restrictions for character creation are still in place, though--can't make an opposite-faction DK on a PVP server, can't roll a DK on a server closed to transfers unless you've got a 55 there already, etc. All fair!
Before you ask why this feature wasn't implemented from the get-go, remember that it wasn't even very long ago that the developers were deciding "how is dk formed?" (though they did say that the restriction would be lifted soon after Wrath launched).
So fret not, ye oppressed. Soon, your chains (of ice) will be broken.