It's a bold move to follow up a well-received product with one that looks absolutely nothing like the first, but just take a moment to look at that cover. It's amazing. As to the content, this is a worthy successor to Adversaries & Allies in Baldur's Gate, providing a wealth of material - and, of course, tons of NPCs - for games set in Chult. Plus it's formatted for screen reading, which is awesome.
The level of detail given to each of the NPCs in this product is fantastic. It focuses on their history, personality, wants and goals, providing enough information for you to drop these characters into your game with a minimum of effort without swamping you with too much to take in. There are helpful suggestions for incorporating each NPC as either a friend or a foe, and the addition of some trinkets and personal effects is a nice touch. The suggestions for which NPC stat blocks to use in combat provide a nice way for you to take seemingly vanilla enemies from the core books and liven them up into memorable additions to your game.