If you've not yet read about the general changes in the 1.4 beta line, now is a good time to do so. It's expected that we'll stay in beta for the new features until we release the 2.0 version of the game in late August, alongside the new Nihon no Mura expansion. A lot is different in the base game since 1.4, so we want to make sure and give this time to mature before we put this out to everyone.
This one mostly is tuning. The god-related mythological creatures have way better costs now, and the resource building upgrade progression makes sense now. Beyond that, just a few minor fixes and typo corrections. Things are looking good!
This release is the third "release candidate," which basically means we're into fine-tuning-only mode until this launches next week. Probably Wednesday the 28th, but we'll keep you posted!
This is a standard update that you can download through the in-game updater itself, if you already have any version of the game. When you launch the game, you'll see the notice of the update having been found if you're connected to the Internet at the time.