NC Soft has announced that City of Heroes and City of Villains North American servers will be taken down for maintenance on Wednesday, May 28th:

On Wednesday, May 28th starting at 6 AM Pacific (9 AM Eastern) the North American City of Heroes / City of Villains servers will come down for maintenance. The downtime is expected to last 2 hours. The purpose of this downtime will be to upgrade the servers to version 17.20080521.1 that is currently in testing on the US Training Room.

Click HERE for the patch notes.