Yeah, that is a huge problem with elance, etc.

Two things I've been thinking about

1) Invite only referral system - You only get in if someone vouches for you -- keeps quality up, probably keeps your cost up as well, if you want bottom of the barrel you go to one of the other places.

2) If it ends up being completely open, then people can sort by third-party signals (github followers, stackoverflow karma, quora karma, linkedin connections, etc.)

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