This week, in an interview with Nicholas Carlson of Business Insider, Google's (NASDAQ:GOOGL) Bradley Horowitz ripped Facebook (NASDAQ:FB) as a "social network of the past." At issue is Sponsored Stories -- drive-by ads that are thinly disguised as posts.

"When you and I are having a conversation, the least opportune thing you can do is have some guy with a sandwich board run between us and try to sell me a sandwich," Horowitz said. "I'm trying to connect with someone and communicate in that sacred space. It doesn't matter if I like the sandwich. ... That is the wrong moment to dangle a sandwich in front of me."

Since Horowitz is front man for the Google+ social network, investors should take his comments as nothing more than fearful admiration of a rival. Yet that, too, is telling. Horowitz and his colleagues have good reason to fear Facebook, as Fool contributor Tim Beyers explains in the following video.

Fool contributor Tim Beyers is a member of the Motley Fool Rule Breakers stock-picking team and the Motley Fool Supernova Odyssey I mission. He owned shares of Google at the time of publication. Check out Tim's Web home and portfolio holdings, or connect with him on Google+Tumblr, or Twitter, where he goes by @milehighfool. You can also get his insights delivered directly to your RSS reader.

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