http://www.mercurynews.com/business/ci_18671416For months, debate has raged about whether Silicon Valley has been experiencing another bubble that can't possibly be sustained. The frenzy is obvious: New figures from the National Venture Capital Association show more venture money poured into Internet startups last quarter -- $2.3 billion -- than in any period since the dot-com bubble, driven largely by investments in social media companies.
But even as investors race to find the next Facebook or Zynga, the celebration could be short-lived. Two recent surveys of venture capitalists and investment bankers -- the very people poised to grow rich off a new wave of tech stock offerings -- show them increasingly wary that the social sector is becoming too risky. And the stock market sell-offs that have buffeted the tech-heavy Nasdaq index this month sharpened those concerns.
"Those of us who lived through the dot-com bust are very leery about investing in social at these valuations," said Paul Santinelli, a venture capitalist at North Bridge Venture Partners, referring to the premium venture firms have been willing to pay to get into hot startups.
... Stock analysts -- including those from two of the three firms that underwrote LinkedIn's IPO -- have said the professional networking site can't sustain the revenue growth to justify its lofty valuation. It was just the second time in more than a decade that a U.S. company saw its stock downgraded by two of its lead IPO managers within 90 days of going public, according to Bloomberg News.