Hi,
Today I will be migrating the mailing lists from a very old server (lily) in Amsterdam, to a new server (sodium) in our new Ashburn data center. Mailman will be upgraded to version 2.1.13 along the way.
During the migration, mail will be delayed as all data will need to be transferred to the new host. No mail should go lost, but no new mails will be sent out during the process until done, and the web interface will be unavailable. This shouldn't take more than one hour, if all goes well.
I will report here when things should be back up and running. Afterwards, please let us know of any new issues, in bugzilla or on IRC (#wikimedia-tech). We don't expect any problems, but as with any software upgrade or migration, this can't be guaranteed...
Thanks,