Mage
Frost and flame from a distance. Blizzard has not published its mage changes yet, so this page is short.
Blizzard's description of the mage is a frail wizard who would rather not be hit, "hurling powerful bolts of frost and flame" from range. Mages also bring Polymorph, which takes one enemy out of a fight for a while. Blizzard has said that kind of crowd control still has a place in Forever's dungeons.
Pick it if you like standing well back and seeing large numbers.
Who can be one
Alliance: Gnome, human, High Order Skyborne.
Horde: Orc, troll, undead.
What to wear
Armor: Cloth.
Look for: Intellect, spirit.
Weapons: A staff, or a dagger with an off-hand item. The guide's testers argued about which and called it a matter of style.
For once, the weapon. Then intellect. The gear guide has the rest.
What we don't know yet
There is no Blizzard deep dive for the mage yet. We don't know what has changed in its spells or talents, and we will fill this in when Blizzard says.
Crowd control means switching an enemy off for a few seconds so the group can deal with the others first. Mages are the best known for it.
Where this comes from
How we verify- Blizzard
The class description, and which races can be mages
Blizzard: Create the Hero You Want to Be (races, classes and racial traits) - Blizzard
Polymorph and similar tools still have a place in dungeons
Blizzard: Deep Dive panel recap - Not confirmed
What has changed for mages in Forever
No Blizzard article on the mage as of our last check.

In the 2004 guide
The 2004 guide gives the mage 10 pages (pp. 110–119): a short story, an introduction, starting attributes by race, ability tables, talents and strategy.
We have no then-and-now entries for the mage so far.