I continue to stand by this theory. However, for those looking for direct exposure to publicly traded social media companies, PBS has become another fund to keep on the radar. Representing over 3% of its portfolio, LinkedIn has managed to earn a spot among the fund's top 10 holdings. This is an important week for this young, professional networking company. During the latter half of the week, the firm is slated to report its quarterly earnings performance alongside the companies mentioned above. Written by Don Dion in Williamstown, Mass.