[steven]

I have to say though... if this is said as more of a statement than a question, ie: What's that guy wearing?! (as in he looks goofy), then I don't believe どんな格好している would be appropriate (maybe you could say something like　何格好しているのかい）or something like that? In that kind of situation I've heard things like その人何着とんけ？ which means in standard Japanese, I would guess something like その人って何着ているのかい？！ or something like that. Of course this would all be said in a joking manner between friends or when making fun of someone on TV who is purposely dressed funny as this kind of language would be innapropriate to use with people who you don't know too well.

I know it's technically not correct to say 着る for things other than shirts/jackets/sweaters etc., but I've seen Japanese people do it quite frequently. This is probably like 5% of the time (which is a guess), but it's still noticable to me. Maybe it's just my wife though... sometimes I think she makes mistakes in Japanese as much as I do haha.