To skip the crossdressing theme for a moment, another reason I went for white is that there are some really nice design details on the Mk5 gti which white shows off best.
Specifically, the front has a lot of black plastic which on a car with rubbish attention to detail would be best hidden with black, but since the design is so good, white is the best to bring it out.
Then there's the way the recesses where the wipers go becomes shallower as it progresses up around the windscreen - or the way the same thing happens around the inner edges of the headlights near the grille. you only really notice these things on the white car. Then there's the shape of the windows - it's a really strong part of the overall design, and a light colour is needed to bring this out... it's a shame they've ruined the line around the back windows (the seal on the inside breaks the line from the front window).
Basically, I think black is best for cars where you want to hide the design of the bodywork, but the golf is unusually well done and these features need showing off! (compare with the godawful peugeots right now

which look best when covered in a sheet )
Final argument for white is that it makes the golf look like what the stormtroopers on star wars would be driving. Surely that's the most important consideration?

