Yeah, there are quite a few notable startups and a strong community that is growing very quickly. Just had Startup Weekend in Orange County with another planned for March and one in LA in January.

Some solid Tech Meetups: - OC: http://www.meetup.com/OC-Tech-Startup/ - LA: http://www.meetup.com/Los-Angeles-Lean-Startup-Circle/ - SD: http://www.meetup.com/SanDiego-Tech-Founders/

I'm down in Orange County so I'm more involved in the community here with startups such as Mavenlink, Catchfree, and Drumbi. If you're going through LA, I strongly suggest stopping by Coloft.

If you have more questions or anything, let me know.