Threads of Fate Mode in Shadowlands

 Blizzard has a new system for players who have completed the 50-60 Shadowlands campaign. To be clear, you just need to finish the final story quests in Revendreth (not counting the Venthyr covenant) to qualify for this, and I'd assume you also have to be level 60 (while one would think that completing said quest should get you to 60, when I did it, that was not the case. Here's hoping that's fixed come October 27th.)

You'll still need to complete the Maw intro quests, which is enough to get you to just shy of 51 (I'd say it's 45 minutes of questing, roughly) but the moment you arrive in Oribos, you get frozen in time and the Fate-Scribe comes and offers you two options: to simply repeat the story quests and do the zones in a predetermined order, or to go with the "Threads of Fate" mode, which scales all the zones and lets you do them in any order, as well as having you choose your covenant immediately.

Like the level 60 quest, you do get some target dummies and the ability to test out the covenant abilities before you make your choice, but once you do, it's locked in, requiring a bit more effort to return to a covenant you abandon.

With the covenant chosen, you also effectively have the story campaign completed as well - you don't actually get to do the main story quests for the four zones, or the various trips to the Maw.

Instead, when you arrive in your chosen covenant's zone, you'll get quests telling you to complete objectives around each zone to earn the favor of the various factions/covenants in those zones. These quests, along with new bonus objectives, as well as all the side quests in those zones, are what you'll be doing to actually level up.

The big "blanket" quests for the zones say you should get credit for doing side quests, killing dungeons bosses, killing rares, and completing bonus objectives, but my brief experience with it showed that not everything was awarding credit (though as a new system, that could just be a bug.)

While I do like being able to choose the order in which I do zones, I'll be honest and say that I'm probably going to stick with the main leveling path for at least the first few characters I bring through Shadowlands. Getting to test out your covenant ability over the course of a whole zone's story is a pretty good way to get a feel for it and whether you want to use that (while I don't know what is simming for most powerful, I've found that I'm pretty happy with the Venthyr Death Knight ability, and I also find it fits thematically for my ancient draenei. I actually found I liked the Night Fae Demon Hunter ability better, even though my plan is still probably to have him go Necrolords. My Paladin (who's actually my main and will probably go through first) is leveling the story-mode way, and I actually really like the Kyrian ability, which is also a pretty Paladin-appropriate covenant, so cool!)