The San Diego Union Tribune has posted a Google Map that shows in real time where the fires are burning, Estimated Advisory Evacuation Areas, and evacuation destinations. Link -via Metafilter
The Los Angeles Times also has a map of the fires around the Los Angeles area, updated every few hours. Link
the title of this post is semi wrong, this isn't showing California fires, its showing the sd county ones, there a other fires higher north that aren't shown.
For SD; KPBS has better, detailed maps which are updated more often: http://maps.google.com/maps/ms?hl=en&ie=UTF8&msa=0&msid=114250687465160386813.00043d08ac31fe3357571&ll=32.990236,-116.930237&spn=0.946815,1.842957&z=9&om=1
Has a map with roll-over highlights for 17 fires in CA.