I'm not so sure I like the idea of players being able to play as ghouls. In Fallout you have always been a human, and the fact that someone will, inevitably, spend their days as a ghoul running around naked in town is not very appealing either... Not to be a prude or anything, but a naked radiation burn victim trying to jiggle his stuff in front of me... I'd have to pass on that.
Seriously though, I hope for a quite detailed character creation system. I always disliked online games where the majority of the population look similar. A creation system where you can make your character look really unique would be highly appreciated. A perk system would also help to make your character have a unique feel I suppose, though from what I gathered glancing around the forum it seems Perks might be given to you automatically based on your choices during character creation. Which is not a bad idea, as long as you can't put it into a system, i.e people all ending up with the same, superior perk.
Just rambling on, I should wrap it up.