So far, the bikers are completely on board. Both the SF Bicycle Coalition and the Bicycle Advisory Committee have offered support and are talking up Bike Class to teach bikers that riding on the sidewalk is bad....mkkkaay. Like what these guys did. The Bicycle Coalition is also sponsoring that "critical manners" thing to help spread the word.
As for the skaters, there's no comment from them, but they've been complaining for awhile that there's no real place to skate in the city so they might as well hit the streets.