That said, the Deck of Many Things, Figurines of Wondrous Power, and Magic Rings are things you can see right now.
Wizards of the Coast has been honest with saying all kinds of things about what kinds of content are going to be in the new Dungeon Master’s Guide, they’ve been downright cagey about the precise specifics of what precisely the rules we’ll see are. No more, with Wizards promising that for certain contributions to its Extra Life campaign, it will release new previews of the recently delayed game book. Previews so far include magic items and the notorious Deck of Many Things, but, let’s be honest, we all just want to see those rules for firearms.
You can see the previews as they’re revealed right here. You can see the D&D team’s Extra Life progress here.