As Lee said, with the coming of Forsaken, the lore has suddenly stepped into overdrive. While CoO was meh, and Warmind revealed more about Rasputin and its origins (and indeed cleared up mystery surrounding the missing Elsie Bray and the Exo Stranger), Forsaken's lore both 'in-game' and in the lore collectables have put the spotlight on a LOT of lore from D1 that people thought was never going to be really touched again.
Even in party chat, I've heard people asking questions like, "Find Toland? Who is Toland?", and I've badly wanted to reply but when you're in Crucible or in a strike or getting whiffed out of existence by yet another bloody Sleeper in Gambit, it's never really been the time/place to start delving into the (surprisingly) extensive lore surrounding even 'small' questions like that.
Feel free to post your questions in this topic, big or small, and I'll either answer them there and then or if I feel it's too big a question, make a topic on it.
In the meantime, I am planning out two topics at least, both dealing with current events that are getting a lot of speculation and discussion. The first will deal with Savathun and her plans with the Taken and what the Last Wish was all about. The second will be surrounding Dredgen Yor, Shin Malphur, the Shadows of Yor and of course, our favourite rogue in the form of The Drifter.