Emilia Fazzalari and Wyc Grousbeck (married couple, he owns the Celtics) are picking up the tab for the footbridge. It'll be the "Fazzalari Sky Bridge" and will open in September.
Had a little conversation with one of the crew who informed that the crane, next to the core, will be jumping up two floors and a load of 17 steel beams will be arriving this weekend. Should start to see steel rising next week.
As you can see they have removed the southern portion of the staging platform and are removing more of the old building on the eastern side of the site.