It looks like Riverside is on board for CSTS 2009!!
The SoCal Browncoat Yahoo Group lists the following updates for screenings:
Can't Stop the Serenity 2009 Los Angeles - June ?
Can't Stop the Serenity 2009 Orange County - June ?
Can't Stop the Serenity 2009 San Diego - June ?
Can't Stop the Serenity 2009 Riverside - June 23
http://tv.groups.yahoo.com/group/SoCalBrowncoats/Woooot!!