When Charles Soule started his Daredevil run DD's secret identity was back in the closet, with only Foggy Nelson knowing who he really was. Today's issue revealed what caused the new status quo.
Daredevil visits his girlfriend Kirsten, from Mark Waid's run, but she doesn't know he's really Matt anymore.
Maybe this was explained elsewhere, but I think there's a little discrepancy with how the mindwipe thing was supposed to work. Before it was shown that Elektra remembers being with both Matt and Daredevil, she just thinks they were two different people and that she was cheating on Matt. Here Kirsten only remembers being with Matt.
Daredevil visits Foggy, who doesn't remember who he is either until he unmasks.
Daredevil goes back to the Purple Man's machine, only to find it destroyed. He fights some crime and sees that nobody else knows who he really is anymore either.
Matt breaks up with her.