I've heard tales of Cruise autonomous vehicle pileups but never witnessed one until today. While heading to a meeting, I encountered six Cruise cars obstructing the northwest corner of Brannan and 3rd in SoMa. This interrupted the flow of traffic and led other drivers to dodge them by veering into the bike lane and even into another lane of traffic, as one Cruise vehicle had stopped partially in a lane of oncoming traffic with its wheels turned. I'm uncertain about that car's intended turn, especially since it was poised to make a left onto 3rd which is a one-way street. It was hazardous, frustrating, and unsettling.
I admire Cruise's mission and have immense respect for Kyle Vogt and his team who are fast-tracking a safer automotive future. Most recently I proposed to him that they consider developing a site where citizens can learn about incidents and read a post mortem response to each of them. For me, transparency like that would significantly increase my comfort level with Cruise.
In the meantime, the folks running Safe Street Rebel are tracking AV incidents based on reports. Unfortunately, it's difficult to gauge their frequency, identify their causes, or understand what steps are being taken to prevent recurrence.
In the event you want to report an incident to Cruise you can reach them directly at firstname.lastname@example.org.