Levelling a Death Knight from level 1 wouldnt make any sense whatsoever. I agree with their idea of a 'Hero Class', Death Knights are supposed to be powerful already due to their former connection with the Lich King. The quest idea is nice, I really want to play an evil-themed quest area and earn Death Knight gear; you can bet the final quest gives you a badass Runeblade... which of course you will replace with the ugly Rage Reaver the minute you enter Outland :(
Taking a little ************ lore-fetishist aside here, the other classes, in general, are classe that could at least theoretically arise from the general population. Hunters, Warriors, Rogues etc are basically mercenaries and everyone has to start somewhere. Priests and Druids are equally obvious, they would perform a function in society even if they only had Rank 1 Renew.
Death Knights though... I don't really see how you could have a Level 1 Death Knight. What was he doing before he decided to go find his fortune in Outland? Trimming the hedges with his 4DPS white-quality Rune Blade?
I personally am looking forward to the RP-server Death Knight character descriptions... every emo-RP fanatic is gonna roll one, Death Knights all have a tragic and shrouded past by definition.
~sin