The subterranean connection, which is now available at 41 stations at no cost, played host to one million tweets, Facebook posts, emails and web pages between June 25 and July 1.
Virgin and Transport for London (TfL) are planning to expand the service to 120 stations by the end of the year, though charges will be introduced in the autumn.
"Londoners and visitors are loving our new WiFi service and we're on track to connect Tube journeys right across London ahead of the Games," said Kevin Baughan, the firm's director of metro wireless.
"With millions of smartphones, gadgets and devices taken onto the Tube each day, the demand for data continues to grow and we're rolling out a future-proofed service that makes superfast wireless connections the standard.
"In partnership with TfL, we've achieved a huge amount and have launched a service London can be proud of."
To use the WiFi service, London Underground passengers need to connect the service and register their email address.