Facebook's users turn up their noses at its adsToday, I don't think Randi Jayne, director of market development at Facebook and sister of CEO Mark Zuckerberg, would sing quite so gleefully about "startups [that] get the rag ... from Valleywag." Because now comes her employer's turn. The Reach Students blog notes that a campaign on Facebook drew a 0.04% click-through rate — a dismal response that's far from uncommon in advertisers' experiences. No wonder the site is scraping the bottom of the barrel to find advertisers. If Zuckerberg is to maintain his site's precious independence, he will have to figure out better ways for his company — and its advertisers — to profit from its rapidly swelling user base. Should he consider placing ads on his sister's show tunes instead? They'd get better click-throughs.