The Office Service Pack Team announced Service Pack 2 for 2007 Microsoft Office System. This new service pack will be released between February and April 2009. It will contain both client and server updates. At a high level it will contain the following for Project Server 2007: Improvements around processing status approvals from Office Project Web Access into Office Project Professional 2007
For SharePoint specific updates check this initial post: http://blogs.msdn.com/sharepoint/archive/2008/10/24/prepare-for-the-upcoming-office-sharepoint-server-2007-and-windows-sharepoint-services-3-0-service-pack-2.aspx
Stay tuned for more information.
Christophe has posted the links to the October Cumulative Update for Project and Project Server 2007
The December Cumulative Update was released on December 16th. The next Cumulative Update (CU) is scheduled
With the recent publication this week of this Project Portfolio Server 2007 document: Project Portfolio