Either the short white or the long black. I definitely like the body design especially the placement of the old personality cores on the suit and it's very nice to see a human-GLaDOS that doesn't look to cutsey and anime-ish.
Short white sounds good, I always imagined GlaDos as a no-nonsense women, and short hair suits that role. ^^ I love her little "purse" carry on module. Silly Rei, why are you still talking on here while there is science to do? :3