I just saw a blurb in the newspaper the Federal IRS business travel rate is dropping for 2010 to $0.50/mile. This will also drop California's w/c mileage rate per DWCNewsline 86-07 from the current $0.55.
Here's a link,
http://www.dir.ca.gov/dwc/dwc_newslines/2007/Newsline_86-07.pdf
Stew