From the piece on sfgate.com, the online version the SF Chron:
"No candidate has ever used all of these tools at once - and it had to happen with a candidate from the Bay Area. This is the capital of new media," said Newsom's political consultant Eric Jaye, who noted that San Francisco-based Twitter, Palo Alto-based Facebook and San Bruno-based YouTube, now a subsidiary of Google, are all located in the region.
Jaye said the mayor has amassed some 270,000 followers on Twitter - second only to Gov. Arnold Schwarzenegger - as well as 40,000 on Facebook, 150,000 names on his campaign e-mail lists, and reaches thousands of others with his regular blogs on the Huffington Post and Daily Kos, two progressive Web sites.