I was downtown last Friday and got a look at the construction activity on the old Filene's site:
One thing that I'm not clear about: this building seems to be set back much more than the old one was. I don't know if there will eventually be a larger parcel of open space there, or if another, lower portion of the building is going to be constructed closer to the fencing.
Update: To satisfy my own curiosity I dug around a little, and the revamping of the old Filene's "Burnham Building" is what we're looking at in the picture above, but that's only one part of the project, the part where the retail will go. The much larger portion (56 stories, 625 feet), where the residential units will be, is going to be built in front of this structure, so while its footprint isn't that large, it makes up for it in height. Those areas covered by yellow are where the two buildings will be connected eventually.