Passion. Engagement. Curiosity. Being the absolute best possible at something - I don't really care what, but being mediocre at lots of things is a turnoff. Ability to learn new stuff, more so than any specific skill (although YMMV with this one).

Any interview I walk out of thinking I've had a 2-way meeting of minds, a genuinely engaged conversation as if we're already peers, rather than an attempt to simply answer a list of questions is going to do well.