All U.S. servers will come down at 7am PDT on Thursday, March 15, 2012. Estimated downtime is one hour. Here are the patch notes:

GENERAL
You will now be told to relinquish your player made dungeons before using the character transfer token.

TRADESKILLS
Several new sets of housing building blocks have been added to existing ‘carpenter essentials’ recipe groups.

ITEMS
The maximum scaling size of all building blocks has been increased.

Source: EQII Forums