95% of blogs are abandoned

"According to a 2008 survey by Technorati, which runs a search engine for blogs, only 7.4 million out of the 133 million blogs the company tracks had been updated in the past 120 days. That translates to 95 percent of blogs being essentially abandoned, left to lie fallow on the Web, where they become public remnants of a dream — or at least an ambition — unfulfilled."
Source: New York Times, 5th June 2009, citing this original research from Technorati