And guys, I'm excited.
Return to Karazhan will introduce a new 5-player dungeon with nine - yes, nine - bosses. The old Karazhan is not going anywhere, though, so don't worry if you have things to farm there or, just, you know, like to hang out there.
With the new Mythic+ system, new dungeons don't need to have inherently better gear than old ones, so this should be added to the random rotation (though I might recommend Blizzard splits it in two, as nine bosses is quite a lot - it'd be the largest dungeon since Vanilla.)
But that's not all!
7.1 will be introducing a new raid in Stormheim that fits in between the Emerald Nightmare and Nighthold - it appears this raid will be a small one.
We'll also be getting some additional outdoor content in Suramar during the patch to develop the Nightborne story.
This planning ahead strategy is very promising. You'll recall that Mists of Pandaria had really great patch pacing (until Siege of Orgrimmar lasted forever,) and I think Blizzard is trying to do the same for Legion.