During Sony’s Q1 09 earnings report, CFO Robert Wiesenthal revealed that half of PS3 users have signed up for PSN.
“I think it’s running on track, and we are expecting really great things this year from it,” he said.
According to Kotaku’s calculations, there are 23 million PS3 consoles out there and if half have signed up, that means there are currently 11 million people using PSN.
Currently, Sony measures sign-up rates for PSN by the number of individual accounts.
More through the link.