“We are aware of the lag issues occurring in the new U20 regions and are working on a solution,” the studio said on the forums. “We will be making changes to live servers shortly in response to the lag seen in areas of the Update 20 landscape. We will continue to monitor both client- and server-based lag from there, and are planning a patch for early next week.”
On an Update 20-related note, players commented on the quality of the promotional artwork for the patch. SSG informed the community that it had commissioned renowned Tolkien artist Ted Nasmith to create the illustration and that a wallpaper version will be forthcoming.
Source: Official forums #1, #2
