Do you guys really 'tame' your hair for an interview? I would never do that. I believe they should hire you no matter what your hair looks like. If they judge you on your hair, are they really worth it? I don't think so.
I always let my hair down when I have an interview, also i'm not planning on doing updo's when i get the job.
But i guess that's just me. (I have an attitude when it comes to my hair, i'm sorry)