Somehow unsurprising; also see Big-Name Investors Back Effort to Build a Better Bitcoin (MIT Technology Review) and Introducing Ripple, a Bitcoin Copycat (Bloomberg BusinessWeek)
"The Winklevii, as they are known, have amassed since last summer what appears to be one of the single largest portfolios of the digital money, whose wild gyrations have Silicon Valley and Wall Street talking. The twins, the first prominent figures in the largely anonymous bitcoin world to publicly disclose a big stake, say they own nearly $11 million worth.Never Mind Facebook; Winklevoss Twins Rule in Digital Money - NYTimes.com
Or at least $11 million as of Thursday morning — when trading was temporarily suspended after the latest and largest flash crash left a single bitcoin worth about $120 and the whole market worth $1.3 billion. At one point, the price had plummeted 60 percent."