Investing.com - Facebook (NASDAQ:FB)'s stunningly disappointing earnings drew more than a quick and vicious stock market selloff. At least half of the Wall Street firms covering the company promptly slashed their 12-month stock price targets, according to FactSet.Nomura Instinet's was among the largest cuts--20%. The firm echoed others in saying that there is now too much "uncertainty" about the company.Several of the Wall Street firms with the highest forecasts trimmed them significantly. Cowen & Co., Stifel, Raymond James and Jefferies all made cuts between 10% and 20%Still, of the 47 firms with ratings on Facebook, only seven have either a hold or sell rating, according to FactSet.Markdowns aside, Wall Street wasn't all doom and gloom about Facebook's disappointing sales and profit outlook.Everscore called the one-day, 19% decline "a great buying opportunity."BTIG was even more upbeat, saying "investors were overreacting."Facebook shares are now unchanged for the year.