Mischa Barton, Rosario Dawson Dial Up T-Mobile

T-Mobile and Google’s Android-powered G1 phone was launched with star-studded parties in both New York and Los Angeles last week.

Attendees included Brittney Snow, the charitable Mischa Barton, diva-marrying Nick Cannon and hot lunch date Rosario Dawson.

“Combining the best of a mobile phone and the Internet, the T-Mobile G1 with Google provides everything you love about the Web in a pocket-sized phone,” said Andrew Sherrard, vice president, product innovation, T-Mobile USA at the event.

Jack White’s band the Raconteurs rocked the Hollywood party. Sadly, Cannon’s wife Mariah Carey didn’t do the same on the other coast.

Maybe she’s still partied-out after Nick’s 28th b’day!