The Mission's stretch of Folsom Street, between 19th and 24th Streets, just got safer with bike lanes and a road diet striped along with a road-repaving.
Formerly two general traffic lanes in each direction, the street now consists of one bike lane and one general lane on each side, resulting in a calmer environment and extending the northbound bike lane all the way from 24th to the Embarcadero (Folsom turns into a one-way street at 11th Street).
The redesign was approved back in spring 2011, and these improvements are intended to be "short term" measures in the Mission Streetscape Plan, laying the groundwork for the long-term construction of green medians, though that median space doesn't appear to be included in the new layout (there's only a double yellow line down the middle of the street). It could be that the geometry will be re-arranged again once the medians are constructed -- we'll check in with the SFMTA and Planning Department.
Additionally, this stretch of Folsom is set to get bus bulb-outs at six corners, and green wave traffic signal re-timing is set to go in on Folsom between 15th and 24th by next spring.