In 2010, 300 people attended a mashable.com social media meet-up hosted by the Orange County Register. A year later, the number of attendees was around 800.

Needless to say, the paper is expecting an even larger number to come together for the third annual staging of Social Media Day OC, set for June 29 at the paper’s Santa Ana headquarters. Speakers will include media executive Bryan Elliott, who hosts a video series syndicated by Mashable, and Chapman University marketing professor Cory O’Connor.

The event runs from 2 p.m. to 6 p.m. and will feature a now-familiar staple of such SoCal meet-ups: LA food trucks. Attendance is free, although more formal RSVPs are required for the breakout sessions.

To find out more and-or sign up, click here.