I picked up Van Richten's Guide to Ravenloft and have been reading it cover to cover. This is my review of the book, chapter by chapter. Chapter 3 covers over 30 domains, so I'm posting about it as I work my way through the different domains.
The first domain described is also the most famous. Barovia is home to Strahd von Zarovich, the first vampire and subject of Expedition to Castle Raveloft, Curse of Strahd, and many other (most?) Ravenloft adventures. On the one hand, Barovia couldn't possibly be omitted from this book and yet on the other hand, it seems almost silly to have just 6 pages about it when entire source books on it exist. As you'd expect, Barovia is by no means sufficiently described in these 6 pages compared to the 250 pages of the 3.5 Ravenloft Campaign Setting, the 200 pages of Expedition to Castle Raveloft, a gazeteer, and an assortment of Van Richten guidebooks.
I feel like this section would have been better used if it contained some cool artwork (because why not?) along with the words "See Curse of Strahd." In effect, that's what this section is, anyway. It provides you with the general feel for Barovia (it's Gothic horror in an Eastern European style setting.) It briefly mentions Madam Eva, Tatyana, and a few other major characters and locations, although I have no idea what you're meant to do with this information. If you tried running an adventure off of what's provided here, nobody familiar with Ravenloft would recognize Barovia because you'd have to make up most everything from scratch. There's nothing wrong with making stuff up about an imaginary place, and you could always fall back on that as an argument when somebody points out blatant inconsistencies with the versions of very significant locations and NPCs based on the sliver of information you manage to infer from this book.
I think it would have been a far better use of 6 pages to present a Barovia in which Strahd isn't the driving force of the adventure. After all, if you want to run a Strahd aventure, you're going to run Curse of Strahd or one of the historical modules featuring Strahd, or else you're familiar enough with Strahd that this book isn't your source material anyway.
So why not spend 6 pages presenting us with heretofore unknown locations in Barovia?
The problem with this section is that there's no stat block for Strahd himself (page 68 says "His statistics are similar to those of a vampire," so in other words "See Curse of Strahd), and there's no map of Castle Ravenloft. It's silly to pretend that a Dungeon Master is going to read this section and be equipped to run a game in the Barovia that everyone already knows. So I wish they'd just given us building blocks for a new Barovian adventure, one in which Strahd drops in every once in a while to terrorize the party, but maybe he's staying in his summer home, or he's searching for something out in the Svalich Woods, so that the party never has reason to visit his castle. The introduction hints at a "new generation" inheriting the monster hunting tasks of Van Richten, so why not use one or two of them as a vehicle to introduce some new corner of this dreadful domain? Or why not explore a subtlety of Barovian lore that hasn't been fully explored in earlier books?
I don't understand the purpose of this section as written, and I wish it contained unfamiliar parts of Barovia rather than an obligatory mention of just enough content to boil down to go buy Curse of Strahd.
This section is, admittedly, a victim of Barovia's infamy. The only reason I think it's too light on detail is because there are so many details out there already. In a way, this is the worst of 5e, and it's the kind of thing I saw in Sword Coast Adventurer's Guide. They take a setting established throughout hundreds of pages in several volumes, and they compress it down into a page or two summary. I don't understand the value of that. I'll gladly go buy a source book from an old edition to learn about a setting, but I bought the new setting book without the understanding that it's just a summary of the old ones.
Aside from being confusingly sparse on useful information, there are some great story ideas and tables in the Barovia section. Strahd's eternal goal is Tatyana, so this section has a d8 and a d6 table with ideas on the role that Tatyana might play in a Barovian adventure. There are other tables with stories and plot hooks.
This was a disappointing start for Chapter 3, as I'd really hoped for new Barovia content. But next is Bluetspur, a cosmic horror realm with the benefit of having been as underdeveloped as Barovia is developed. Whatever information this book has on Bluetspur is bound to be new.