Lyft's approach to self-driving partnerships in general seems to rest on the assumption that self-driving providers will catch up to each other before any of them can fully handle everything a human driver can do. If this assumption is correct, Lyft ends up in the great position of being compatible with all major self-driving providers before any of them can feasibly launch a standalone service without Lyft's driver network (who wants to take a car service that doesn't take you downtown? Or doesn't work in the rain?). Ideally, this means Lyft can negotiate favorable terms with all the providers and maintain their position as marketplace brokering between riders and ride providers (either human or robot).
But, if this announcement means Waymo is truly way ahead of the competition, is Lyft aiding and abetting its own demise by covering Waymo's short-term holes (weather, urban areas, etc) up until the day that Waymo can cut Lyft out and run their own service? If Waymo is the only self-driving game in town, and they solve the urban case, why do they need Lyft? I wonder if we'll see any tension develop between the two if leadership at Lyft starts to get concerned about this scenario being a likely outcome.