There is an email list called "E2" for the "E2 development team." The address is e2@lists.wikimedia.org. No such team (the former Editor Engagement team) exists anymore, but the Collaboration Team has been using that list as our mailing list. This has various disadvantages. In particular, the list name is completely mysterious and undiscoverable by anyone who may wish to email Collaboration Team.
I am reliably informed (thanks James!) that renaming lists is not really a thing. So let's just deprecate or forget the old E2 list and start a new one called Collaboration-Team
Please make Joe Matazzoni and Roan Kattouw the admins. Thanks!