The O.C. (2003 - 2007)
Frothy, self-aware soap opera nonsense with an above-average cast. The tone is similar to Veronica Mars which came out the following year.
Trivia: I'm almost finished with season 1 and I find it amusing that the only scenes actually filmed in Orange County are second-unit helicopter shots, everything else is filmed around Malibu, Santa Monica, Marina Del Rey, Manhattan Beach and Brentwood...all firmly within L.A. county.