Polygon covered this with an
article.
Prior to this, 5E had seen a release of Curse of Strahd, a 200+ page hardcover adventure which updated the venerable Castle Ravenloft adventure. This by itself wasn't particularly big news, since 3rd and 4th editions had also both published an adventure update without going into the setting as a whole.
Azalin, one of the main characters in the Ravenloft setting, was teased as an NPC group patron in
an earlier product. But this is the first confirmation of a setting wide treatment for Ravenloft ever since the 3rd edition licensed it out to White Wolf's Arthaus studio back in the 00s.
A few points from my reading:
- Several domains merged and rewritten (nothing unusual, this happened a fair bit in 2nd and 3rd editions too)
- Original darklords featured many males and very few females, this edition appears to have several regendered darklords perhaps with a more even gender split
- Some themes rewritten, e.g. the 3rd edition Germanic medieval fascist state of Falkovnia is now a zombie-apocalypse survival domain
- Focus on inclusivity and sensitivity to realworld cultures and other identity aspects. For Ravenloft, this was especially salient given the great amount of attention given to the Vistani ethnicity, a traveling magic-using stand-in for the Romani people.
- Estimated release date in May 2021, usual MSRP level of $50 or so, similar to hardbacks like Curse of Strahd and Tomb of Annihilation.