I subscribe to several niche job feeds. At least once a day, I see postings for “rock star developers” and “javascript ninjas’. Occasionally there’ll be a need for a Ruby on Rails wizard.
I’m pretty sure ninjas and rock stars are too busy being ninjas and rock stars to write code.
If you’re looking for solid talent, write a descriptive ad. Say what it is you’re really looking for, not just ninjas. Know the roles you’re hiring for, understand that (usually) a web designer doesn’t know AJAX, and most web developers (usually) can’t design. If you don’t know the job you’re hiring for, get some advice.