Meeting the parents is a big deal. Maybe not for you, but for me, yeah, meeting his parents was a big deal. :) Looking your best is super important for this type of meeting. You don't want to come across as too high maintenance. You don't want to come across as a hussy (yes, I said hussy). But of course, you don't want to come across as anything but yourself, so here are a few good ideas to play up what you already have. However, no matter what you wear always remember to let your natural personality shine through. Be genuine and they will love you (hopefully :)
When you had to meet the parents, what did you wear?