In all honesty I'd feel a bit disappointed and bad for the Alliance that all they got was a re-skin as a 'new race'. Insult to injury after female Worgen, imo.
I'll never understand folks who just want more of the same. There's already TWO playable Elves in game! I love Trolls, but I'd NOT be pleased if Blizz tried to pass off another tribe of Trolls as a 'new playable race' rather than an additional customization skin with a lore explanation. That being said, with Moira's addition to the Alliance Dark Iron skins should totally be available to Dwarves.