Check out the official forums for the complete run-down. A few notables include: The durations of stage 1 and 2 city siege have been cut in half, many parts of the city are no longer tied to city rank, city rank recovers much more quickly, and the Reikland Factory and Twisting Tower scenarios are making a comeback to provide those not engaged in city siege with something to do.
Many players and bloggers have pointed out that these fixes only address the symptoms and not the core issues related to WAR's RvR campaign. Andy was quick to mention that these are only initial changes and more will be coming (e.g., the Underdog system). Testing of these changes should begin next week so keep your eyes on the Herald.