I have been out of Bitmark a long time now.
Who has taken over development?
And what is the status of development?
Could someone give an old BTM supporter a recap?
OK, but brief answer with some pointers.
You could start your recap on page 118
https://bitcointalk.org/index.php?topic=660544.2340After that you can recap on slack, see the pinned messages. If you want to see more, github & gitbook.
Melvin is lead dev & has done loads.