The land at 700 Delaware is to be totally public accessible. You probably can’t wander through the towers, that’s not what is meant by public access. 700 Delaware will actually reconnect the street grid at that location, creating totally public accessible streets. More specifically, reconnecting Brown street to Delaware Ave. Currently, Brown St. is blocked by by a huge, ugly fence with a bus terminal there and stops at Front St. Thus, cutting Brown street off, where it used to go through. Also, it will reconnect Beach St. which runs between Delaware Ave and Front street there, or at least used to.
Here is the ugly bus terminal, with one of the buildings that will get demoed for the 700 Delaware project (the other building is behind it).
Brown Street shold run right along the side of that building you are loking at. If this project gets a go, instead of the busses, you will see townhouses (Can these be considered "Row Houses") reminiscent of earlier Philadelphia architecture.
Here is a shot from the EL at 2nd & Springarden.