Unbridled enthusiasm is great, it really distinguishes those who have passion for programming and see the magic, and those who do it because they can and it pays well.
The ability to explain topics clearly and concisely as well - I think that's a big indicator of a solid understanding of a topic.
I've blogged about what I look for in interviews here
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.