To support Plaza area businesses open late on Friday evenings, the Sonoma Valley Chamber of Commerce, the Sonoma Valley Visitors Bureau, and the Sonoma Index-Tribune are launching a "Downtown Friday Nights" promotion.  Starting June 5th, two dozen Plaza area merchants will join an equal number of downtown restaurants and entertainment venues in staying open until 8 pm or later on Friday evenings through September.  To join this special Shop Sonoma promotion, contact the Chamber at 996-1033.