We will have a scheduled maintenance window tonight from 10:00pm to 12:00pm PST. The following changes will take place:

10:00pm PST (0600 UTC) border1 Sup720-3BXL upgrade. See http://blog.mozilla.com/mrz/ for more details (this is the second half of Tuesday’s upgrade). During this time all all BGP sessions on border1 will be shutdown and [...]

We will have a scheduled maintenance window tonight from 6:00pm to 12:00pm PST. This is being tracked in master bug 465599. The following changes will take place:

6:00pm PST (0200 UTC) bugzilla.mozilla.org updates. We’ll be updating bugzilla.mozilla.org to pick up code updates. See bug 464713 for more details. Duration 5 minutes.
7:00pm PST (0300 UTC) [...]

We will have a scheduled maintenance window tonight from 7:00pm to 11:00pm PST. This is being tracked in master bug 464743. The following changes will take place:

7:00pm PST (0300 UTC) support.mozilla.com updates. We’ll be updating support.mozilla.com to pick up code updates. No downtime is expected.
7:00pm PST (0300 UTC) Root-level DNS changes.  We will [...]

(Apologies for the short notice.  We generally want to stick to our normal advertised maintenance windows but sometimes technology works against us.)
We will have an emergency maintenance window tonight from 6pm to 11:00pm PST.
The following work will take place:

6:00pm PST (0200 UTC) ) EqualLogic storage array firmware upgrade.  See bug 464458 for details.  We’ll [...]