They're already broken again? I let my AP expire this past November and haven't drive over to WDW since then. The check in side was converted to LED a few years ago and they were looking quite great for a while. The monorail station at MK was also redone with LEDs recently and was looking lovely (same for all the bus terminals). That said, Narcoossees and a building near the kiddie pool have had troublesome lighting for a while now. They're LED as well, but they're much older than the main building (probably done back when the DVC was constructed) and have a bunch of non functional bulbs.
LED's have the potential to last for decades (and the diode themselves generally are reusable), but they require high quality wiring and circuit boards to do so. Most LEDs available to the public (especially newer ones from the past 5 years) have horrible construction and fail very quickly. This is intentional as well, GE are even marketing "longer life" LED's at a higher price point.
Sad thing is that Disney could have avoided this pitfall as the electrical work was likely custom fit and they had better control over the quality that went into it. I guess they skimped on the budget and parts though...