Let's be clear where I'm coming from, here: I've been playing World of Warcraft almost continuously for 15 years. (I lapsed for a big chunk of the Wrath of the Lich King era for IRL reasons.) While I understand the appeal of WoW Classic, I am very much a proponent of modern WoW; the game has evolved over time to be more accessible for me to play just a couple of hours a week, as real life now dictates. But I tend to play solo or just with one or two friends on a sporadic basis, which means I'm looking for something very different than the hardcore raiding or PvP crowd.
Blizzard's new solution in Shadowlands is to return the level cap to its original value of 60 and to make current content appropriate for levels 50 through 60. New players start at level one, and they all play through a new introductory zone built for Shadowlands based on the quest design lessons Blizzard has learned over the years. Once they play through that introductory experience, they can then level up to 50 to catch up with current content by playing through the previous expansion (Battle for Azeroth) right away (from around level 10).
World of Warcraft: Shadowlands marks the eighth major expansion pack for the storied MMO. Judging from a half-hour playing it at BlizzCon this year, it seems like a natural evolution of modern WoW that will run alongside the very-different WoW Classic experience for the foreseeable future. That said, the biggest change wasn't part of my hands-on demo—but don't worry, that won't stop me from geeking out about it in extreme detail.
Claim a covenant's power: players will be called upon to forge a bond with one of four covenants that rule Shadowlands' new zones, setting the tone for their journey through the expansion with a full covenant campaign. As they level up, they'll get new abilities based on their choice, including class-specific abilities for each Covenant—as well as developing soulbinds with specific covenant members, which grant them access to that character's specific traits and bonuses.