There's little excuse for not commenting and none for not indenting. Indentation is handled by most of the best editors and commenting should come as second nature for somebody who MS might like to hire.
They're certainly both disciplines that people get into (either naturally or through schooling) so not showing either, perhaps, shows a lack of discipline, or, at least effort to express it.
Edit: 2 hours for a linked list?! I see he meant now... Fitting in all that formatting in the remaining one hour, fifty minutes would have been pretty tough! (I'm only playing around - I assume there was more to the interview than a linked list!)
