I am a Californian, so I would say yes. Moreover I am from Northern California, which is important to California, as North, South, (and perhaps Valley/Sierras), are the main delineations of Californian sub-ethnicities.
Granted there are further sub-groups within these groups (Bay vs Not-Bay in the north, which is further divided into East Bay/South Bay/North Bay/Peninsula; LA vs OC vs SD vs Valley vs etc. in the South), nevertheless the delineation between North and South is one which exists in reality as Northern and Southern California have their own (semi-)distinct regional linguistic variations ("5" or "Highway 5" vs "The 5", for example), and a trip to a Californian university will reveal that these groupings matter to people, even if only in a half-joking/ironic sense.