Big Bang lead Johnny Galecki opened his account on Sina Weibo, a twitter-like microblogging service popular in China, on Feb.20. Up until now, he has quickly attracted over 30,000 followers on the first day of opening the account.
John Mark "Johnny" Galecki (born April 30, 1975) is an American actor. He is best known for his roles as David Healy in the ABC sitcom Roseanne, as Rusty Griswold in National Lampoon's Christmas Vacation and currently as Leonard Hofstadter in the CBS sitcom The Big Bang Theory.