The closure is a trial program, and the city will presumably re-evaluate the situation again this summer. As of now, Lombard street will be closed on two weekends in June (21st, 22nd, 28th, 29th), July 4th, and two weekends in July (5th, 6th, 12th, 13th).
This is no doubt frustrating for those with hopes of experiencing the street this summer, but it's hard not to identify with the concerns of local residents, whose lives are directly impacted by the swarms of tourists. We'll check back in on this situation upon the completion of the pilot program. If you've never driven down the infamous street, we can personally tell you it is worthwhile, and we suggest you make plans to get it in this summer in case further closures are implemented after the pilot program.