speculation have turned out true this time, Tomb of Annihilation is the name of this event. It will involve undead and dinosaurs, namely the lich Acererak and the setting of Chult in the Forgotten Realms. Here is my thoughts on the announcement and some other commentary on where Wizards goes from there.
First off, I'm sure a lot of people are disappointed in no Darksun or Dragonlance or hey Greyhawk. Well, Greyhawk fans of all things Tomb can add this to their collection no doubt with little effort. I mean, it wasn't all that long ago Greyhawk stole Isle of Dread into the setting (dinos and demons in that case). As to this storyline it's at least a possible departure from the Sword Coast for a while. I see that Pendleton Ward is involved in this story too. As a big fan of the cartoon Adventure Time, I'm a tad disappointed we won't have a D&D crossover with that world, but I do see what Ward's influence will be with ToA; the main bad guy in Adventure Time is "the Lich".
Speaking of liches, I don't know much about the current state or machinations of Acererak, but I'm judging from 5e art, that he is no longer a boring gem-eyed skull on the floor anymore. I also read that there is a variant rule introduced which will make death saves harder. Now that is a good idea! I have not watched the stream yet, but the news flowing in from viewers is positive overall. I'm unsure if this will be something I buy at this time. I'm currently leaning no.
Now onto my past predictions. Over the last couple years I've tried to make odds on what themes and stories Wizards will use/rehash for 5E. After using Ravenloft, Giants, and Demons, they are running low on good ones. So now, in one year with Tales from the Yawning Portal and now Tomb of Annihilation, I have two more themes to scratch off. I had predicted (long shot) a jungle module akin to Cult of the Reptile God, Isle of Dread or Dwellers of the Forbidden City, yet I didn't think it would be visited so soon. Good on Wizards for that decision.
Second, I had speculated Wizards needed to use a lich for a BBEG story. I assumed Vecna, the original archlich, would be that person (of course). However, I underestimated the popularity of Tomb and its ongoing backstory (Annihilation will be the 5th adventure?). With Acererak ascendant in D&D pop culture, I guess a Vecna Lives! redux is not going to happen any time soon. As usual I've been way off in all my top predictions (except giants, no brainer). Expedition to the Barrier Peaks or Gates of Firestorm Peak continues to be my favorites, and I feel Undermountain or another iconic quest like Rod of Seven Parts is inevitable in the next few years.
That's all for now.