I heard this Blue-gray Gnatcatcher as I was walking through the Bodega Dunes today (16 November 2013).
I didn't get great photos, but here are a few for the record. This bird was actively elevating and flaring its long tail, providing views of the white outer tail feathers.
The gnatcatcher was feeding mostly in Coyote Brush (Baccharis pilularis), Bush Lupine (Lupinus arboreus), and California Goldenbush (Ericameria ericoides), sometimes hovering briefly while snatching at insects.
I wrote about gnatcatchers last November, so if you'd like to learn a little more about them, you can review that post here.