Is the upcoming D&D 5e supplement "Xanathar’s Guide to Everything" AL-legal?

Question

Has there been an official statement from Wizards of the Coast confirming if the upcoming D&D 5e supplement Xanathar’s Guide to Everything will be AL-legal? It's due to be released on 21 November 2017.

Answer 1

Yes, effective August 25, 2017. Version 7.0 of the Adventurer's League Player's Guide includes "Xanathar’s Guide to Everything (XGE)" as an available resource. The resource list includes the following:

• Elemental Evil Player’s Companion (EEPC)
• Sword Coast Adventurer’s Guide (SCAG)
• Volo’s Guide to Monsters (VGM)
• Xanathar’s Guide to Everything (XGE)*

You can use races, classes, feats, and spells from the Player's Handbook plus one of the above. The guide also notes (the * in the list) that for the purposes of this "PHB + 1" rule, the "Tortle Package" is considered part of Xanathar's Guide.

It's also worth noting that backgrounds can be from

PHB or any other officially-released Wizards of the Coast or D&D Adventurers League resource

not limited by the PHB+1 rule (emphasis original).

Additionally, a November 9, 2017 post on the official Adventurer's League website further clarifies which options are currently legal, with the note

To be clear: we do intend to more fully adopt this book, but please bear with us while we take a hard look at potential adjustments to our game and organization.

In a nutshell:

• no magic items for sale
• clerics need to pick an appropriate deity for Faerun
• the optional rules for Simultaneous Effects, Falling, Sleep, Adamantine Weapons, Tying Knots, Tool Proficiencies, and Spellcasting are... optional
• random encounters, traps, and magic item awards from the book are nope — instead, use what's in the published AL adventures
• none of the fun new downtime options are allowed
• common magic items don't count as real magic items for the purposes of the AL permanent magic item limit

Answer 2

There has not been an official statement of how Xanathar's Guide to Everything will be implemented in the D&D Adventurers League¹. The reason being is that the AL admins haven't had a chance to look at it, since it's not yet complete. The AL tries to be as inclusive as possible with official Wizards of the Coast D&D products, but we cannot make comments on things we haven't seen in their final form yet.

Source: I am the Community Manager for the D&D Adventurers League, Robert Adducci

^{1 - At the time of this writing, June 5th 2017}

Answer 3

Officially, we do not know yet, but I find it hard to believe that they would not make every effort to include official WotC products

Edit: I used to say unequivocally 'yes', but that was blatantly wrong on it's face given the accepted answer from Raddu to this question , so I changed my answer to reflect what I honestly think is most likely to happen.

There will certainly be limits however. Those limit are set by the AL rules. Currently, the main rule to follow (and that is relevant to your question) is that for any character you create you can use up to two books. The PHB, and one other source book. I doubt that will change, so choose your second book wisely.

From the Adventurers League Player's Guide v5.1 - Storm King's Thunder (link to a pdf) NOTE: This is the latest guide available.

In addition to the Player’s Handbook however, you may also choose to use one other resource from those listed below to build your character.

(emphasis not mine)

And a bit later:

As new player resources become available, they will be added to this list.

• Elemental Evil Player’s Companion

• Sword Coast Adventurer’s Guide

• Volo’s Guide to Monsters

(emphasis mine)

There are also additional rules to consider, for example, currently, flying at first level is not allowed. So a careful reading of the above linked AL rules will be in order to make sure there are not any "gotchas" in the details.

The current rules and other resources can be found here.

These rules are updated seasonally, so there will probably be an update of the AL rules to go with the new Adventure Path, Tomb of Annihilation, that coincides with Xanathar’s Guide to Everything.