Knows how to handle not knowing or getting stuck - some people have a melt down or won't ask for help when they hit a wall or don't know when to push back (we had a vendor that gave us buggy code but kept claiming it wasn't until we pushed back through our management and forced them to let us see the code).
Can visualise the program - how much of a program someone can hold in their head is the only thing I've really seen make a programmer exceptional. It is rare and I've only met a couple of people that can hold a medium sized program in their head, the whole thing this ability lets them basically just vomit it all out into the editor without having to switch between functional and structural context and really does make for a big productivity bonus (maybe as much as 4x).