Caribbean! [official site] is basically 'Mount & Blade With Pirates!', built on the M&B: Warband engine and engaging in the usual open-world RPG faction warfare. But in their haste to leave Steam Early Access, developers Snowbird Games cut a lot of planned features so they could push it out. Turns out, players actually wanted some of those. Snowbird today announced they're revisiting Caribbean! and next month will release an improved, expanded, new standalone version named Blood & Gold: Caribbean! - which will be free to everyone who owns Caribbean! Exclamation mark!
Look over the list of new things in Blood & Gold and you'll notice a lot of them are features cut from Caribbean!, such as multiplayer, female characters, walking in towns, and native tribes. It's got other new things too, like reworked land battles, new special locations, prison escapes, and destructible fortifications during sieges.
Blood & Gold: Caribbean! is coming to Steam and GOG on December 10th. Caribbean! owners will find it popping up as a separate entry in their game libraries.
How come it's a standalone release rather than an upgrade? Snowbird say saves won't be compatible between the two versions, so they wanted to leave the original Caribbean! intact for current players. It'll probably also be nice for them to escape some of the negative Steam reviews, as well as get the store placement and publicity boost of a new release.