Ordinn of Blizzard has posted the following in regards to some gameplay changes on specific servers:

Today’s maintenance removed the boat that traveled from Menethil Harbor to Auberdine from the realms listed below. Two new NPCs, Captain Placeholder in Menethil Harbor and Captain Noteo in Auberdine, have been placed on the docks where players used to board this boat. Both NPCs are marked with a yellow exclamation point over hovering over their heads (the same exclamation point used to let players know that an NPC has an available quest for them). Opening a dialog with these NPCs will allow players to travel between the two cities.

Lightbringer

Cenarius

Uther

Kilrogg

Proudmoore

Hyjal

Frostwolf

Ner'zhul

Kil'Jaeden

Blackrock

Tichondrius

Silver Hand

Doomhammer

Icecrown

Deathwing

Kel'Thuzad

Destromath

Gorgonnash

Dethecus

Spinebreaker