Emergency hotfix will take about 30 minutes.
UPDATE: The servers came back up around 2:19 pm Pacific.
UPDATE: The servers came down at 1:49pm PST with an anticipated downtime of 30-40 minutes.
At 1:23pm Pacific Holly "Windstalker" Longsdale posted on Twitter:
We are preparing to bring the servers down within the hour to fix the broker bug. Downtime will be 30 to 40 min.
She also said that the level 90-95 chat fix is being elusive, and won't be included in this hotfix.