[EBB Sightings] Black-chinned Hummingbird at Coyote Hills nectar garden

My first post to this list . . . today I went to Coyote Hills to look for
the Prairie Falcon (which I found, second tower north of the entry road).
I went on to the park, but was somewhat disappointed to find all of the
usual wetland area dried out.  Not so birdy there.  I did find this girl
at the nectar garden by the Visitor's center,

http://leahy.to/birds/black-chinned%20hummingbird.html

The only time I've seen a Black-chinned Hummingbird in California (I don't
get away from the Bay Area much for my birding).  Is this unusual?  Is she
a wandering migrant who should be in Mexico by now?

				DaveL