rricci, if you look at the two renderings shown on the first page (and first post) of this thread, they do a pretty good job of demostrating how the two rear wings will correspond to the rest of the project. I'm actually glad Yellow mentioned that because I completely forgot there was another component to this project.
I know you all wanted a taller tower here (and more tall towers in Center City) but I actually think this project works
for that cause as opposed to
against it. This project, and others nearby like 2116 Chestnut and 19th+Arch, are what CC Philly needs to ultimately manifest new skyscrapers of considerable height.
I just reexamined an old article profiling this (2040) development before shovels were in the ground, which also had some comments from the developer. He made two excellent points. Not only does this adaptively reuse substandard office space (lowering CC's overall vacancy rate, making it more appealing to tenants and other developers), but it also provides Market West with 24/7 streetlife ...and as we all know here on SSP, the city of today (and tomorrow) thrives directly from that. I think this phase in the history of this downtown will ultimate generate new taller towers shortly down the line and in the process, Center City won't just have more office towers sheltering empty-after-five streets, but a real, bustling, living neighborhood.

Keep it up!