The city is asking for some key obligations on top of this. It's 'enshrining' a reduced fare program for some low-income residents, and it's reserving the right to test dockless bike sharing outside of Citi Bike's expanded coverage area. Lyft will keep Citi Bike's exclusive rights, but it will also have to pay for operating expenses needed to "improve and expand" the system.

The move isn't going to please everyone. Would-be rivals have complained that the city is shutting out competition that could widen your choices. While you have access to competitors in the outer boroughs, you'll have to deal with those ubiquitous blue bicycles whenever you're in a downtown area.

Not that this will deter Lyft. The company was quick to crow that 80 percent of bike sharing rides in the US were from Motivate -- it now dominates the two-wheeled world, and it's about to get bigger with the Citi Bike expansion. And while Lyft is still most closely associated with car-based trips, that will change when it starts introducing branded bikes (newly teased below). Challengers like Uber could face an uphill battle vying for commuters' attention when Lyft has a large head start.