Unfortunately, we currently have no details on the Lich King encounter (warning, spoilers: although we do know how it ends). Look forward to it at some point in the future. For now, enjoy the last dragon bosses we'll ever see in Icecrown Citadel.
Patch 3.3 is the last major patch of Wrath of the Lich King. With the new Icecrown Citadel 5-man dungeons and 10/25-man raid arriving soon, patch 3.3 will deal the final blow to Arthas. WoW.com's Guide to Patch 3.3 will keep you updated with all the latest patch news.