Two permits were issued on March 20
for 1600 Market. One is to demolish the existing building, and the other is to erect a new 24-unit apartment building. Of course, just having the permits doesn't mean construction is imminent, but at least there appears to be some life for this site.
According to this PDF
, the plan is to construct 24 BMR units with 3770 sq. feet of ground floor retail:
Here's a story from several years ago
with an old rendering (for a taller building).