So, you came back eh? We knew you would! You've probably got a ton of questions. Hopefully we can answer some of them right here.
If you left before the Throne of Destiny expansion came out, you'll definitely need the latest setup file. You'll need this new installer even if you have the CDs, due to incompatibilities between the CD installers and current versions of Internet Explorer they won't work. Turbine now offers discounts on multi-month subscriptions. If you're like most people, you'll immediately be trying to find out where you can get the latest copy of Decal and updates for all the Plugins you used to use.
Browse content you missed while you were gone in the Patches section. A list of in-depth articles on a wide variety of game mechanics can be found here.