I made a post along these lines recently, though it didnt recieve much attention. My suspicion is that bungie ninja increased the Gjallarhorn drop rate in the background within the last month or two. It seems like there was a sudden increase in posts by people who had finally recieved it. I myself recieved my first one about a month ago and my friend got his just a couple days ago. I have also seen a few drop during various gaming sessions recently. Nothing certain, just kinda suspicious.