Greetings, Norrathians!
Arcanum Revealed, or Game Update 58, will go live on Tuesday, October 12, 2010. The US servers will be offline at the usual Tuesday update time of 7:00 am PDT and are expected to be back online around 9:00 am PDT.
The update notes are available here in the Update Notes forum, and the feedback thread will be unlocked once the update has been completed on the US servers.