Fortunately, Part Time Druid has some good ideas about how to "fight WoW apathy," just in case you can't think of any yourself. PvP and money farming are in here (those are goals that are practically never ending for sure), and the time-tested idea of going back and finding refreshment in an old alt is a good idea as well. But there are some more original ideas in here as well: helping out lowbies (whether they be 16 or 61) is a good idea, and organizing for five mans might be the best idea. With the daily Heroic quest, there's no better time than now to find four friends who want badges and gold, and set up a regular weekly or even daily time to run a Heroic instance.
Let's be honest: we're going to at least be waiting a whole summer for this expansion, if not a few months after that. Might as well make the most of it -- set some goals now and get productive (or go try out Age of Conan, we're not picky), and the boat to Northrend will be loading before you know it.