[Update #2]: The Shadowlands expansion will be launching for real this November 23rd!
[Update]: Blizzard has revealed the full list of changes arriving with the Shadowlands pre-patch.
World of Warcraft's Shadowlands expansion is set to arrive this October 27th, and in order to pave the way for all of the new content, Battle for Azeroth will be getting a sizable (and final) update in the near future. Sadly the exact date hasn't been announced just yet, but if you're willing to indulge in a bit of speculation, then the Shadowlands pre-patch will most likely be landing on October 6th as that would follow the same pattern as the previous one.
On the other hand, if you're curious about what exactly the Shadowlands pre-patch will even bring to the table, you'll be pleased to hear that Blizzard has now released a lengthy post detailing just that. You can find the full list of changes over at the official website, but for now, here's my very brief summary:
• Character levels are being squished down, with the current level 120 characters going down to level 50
• Item levels and stats are being adjusted downwards as well, much like the previous few expansions
• Exile's Reach is coming as an all-new starting location meant to introduce new players to everything WoW has to offer
• Players will be able to become Mentors and help out newcomers
• Players will be able to level through any expansion of their choice regardless of level
• The barber shop will have a variety of new customization options, including the ability to change gender
• Allied Races will no longer require exalted reputation in order to unlock
• Warlords of Draenor and Legion flying will no longer require special achievements
• The final Battle for Azeroth PvP season is ending soon, though no date has been given just yet
You can also expect a variety of balance changes, class tweaks, bug fixes, and as is tradition by this point, the arrival of brand new bugs to keep you company. In other words, if you're looking to take World of Warcraft for another spin, jumping in with the Shadowlands pre-patch would be a pretty good idea!
Once the update goes live I'll make sure to let you know, and if you're curious about the Shadowlands and its game-defining Covenants, it's also worth mentioning that Blizzard recently released the final cinematic short detailing each Covenant and their goals. Enjoy!