The flares in the New York PVP arena still do not work (in beta and live). This is something that is important to me. They haven’t worked for at least two years now. I know they worked in the first year after relaunch, because I used to use them often to stun other PVPers.
When I first reported it, they just didn’t stun anymore. Now, you can still pick them up, but they disappear out of your inventory when you right-click them. They do not drop at all.