If you find your self interviewing or being interviewed take a look at this post on 20 good questions to ask a web developer.  Overall, not very technical but great set of questions to gauge some things which are as important as technical skills.  Take for example my favorite:

What industry sites and blogs do you read regularly?
This question can give you an idea of how in-tune they are with the latest industry trends and technologies, as well as how passionate they are about webdev. It'll help separate the people who do it as a career AS WELL as a hobby from those who might simply be in it for the big developer paychecks.

I insist on always asking this question.  You always want to look for someone who can keep up with trends and what better way to do that than reading!