A new alpha build is being put on the servers. With it, we're finally getting a new zone and one of the last two specializations is being unlocked, namely Brewmaster Monks.
Much as I suspected, the spec implementation is more about finishing the artifact acquisition questline than the spec itself, so I expect Destruction to come out of the gate relatively functional (though of course it will need refinement.)
The addition of Azsuna is certainly good news, as it takes us another big step toward a complete expansion for testing. I believe all but one of the dungeons is available (assuming there are still two Suramar dungeons.) Should be getting some Naga content (and hopefully lore) in what I suspect will be a pretty cool looking zone.
In addition to these features, some of the Order Hall campaigns will also be implemented. I don't know exactly what these are going to be like, but I suspect that they will be extended questlines specific to each class. I've heard rumors about the Death Knight one that sound pretty cool. Whether these will simply be unlocked on a weekly basis or based on progress through some player effort is unknown (preferably the latter - I think we all agree the 6.1 campaign stuff was way better than the Garrison Campaign, though that's partly just through the plot-significance of the writing.)
However much progress they make in the Alpha, though, I still don't really expect a release until June, after the movie has come out.