According to Dutch site TechTastic, LG has confirmed the update will hit the G3 before the end of the year. The report doesn't name a specific spokesperson, or say how the information was communicated. It's in Dutch too, so it's not easy to make sense from the translated version.
In English, the relevant section reads: "Today LG did to Dutch and Belgian owners of the LG G3 promised that the Android 5.0 update Lollipop before the end of 2014 will be released."
I've contacted LG UK for clarification, and will update this if I hear back.
The HTC One M8 will get Android Lollipop this year. Google is expected to rollout the new OS to its Nexus 7 and Nexus 10 tablets on November 3, which is the same day the Lollipop-toting Nexus 9 goes on sale.
Unfortunately, the Nexus 4 and 5 won't get the update until later, rumours say, though they shouldn't have to wait too long. Google hasn't yet announced a specific release date for the Nexus 6 (all it'll say is November), but it's a fair bet that Lollipop will hit its other Nexus handsets around this time.
Lollipop has a whole new look that's more flat and fluid. It should also increase your device's battery life, support 64-bit architecture, and improve cross-device communication.