TWRP is one of the most widely used recovery solutions in the Android world, and one reason for that is the near-constant addition of new features, such as the upcoming addition of the ability to send system backups directly to your computer via ADB, and a visual refresh to the official TWRP app that brings the ability to back up the boot and recovery partitions. It is important to note that the ADB backup capability, when it drops, will not be initiated through the TWRP GUI; instead, it will be launched through a specialized set of ADB commands, which will differ somewhat in syntax and layout from stock AOSP commands.
Having a working and somewhat recent system backup, referred to coloquially as a nandroid in the world of custom ROMs, is essential for anybody wanting to take full advantage of their device by trying out different ROMs, kernels, and mods regularly. When a bootloop occurs, those without a nandroid handy will have to either flash back to their stock ROM and lose all of their data, or sideload a ZIP file for a new ROM and flash that, which does not always fix the issue that caused the bootloop, or may leave the user with glitches in their day to day use. Many don't keep a nandroid handy due to a lack of available space, since they can run into multiple-gigabyte territory even without user data, so this solution takes the headache out of maintaining up to date backups away from your device.
As for the update to the app, it's live right now in the Play Store. The update brings a new user interface theme that closely mimics the actual TWRP recovery menu, but the under the hood features are a bit more important. The boot and recovery partitions don't often get messed around with and thus most users won't need a backup. They are, however, essential to the function of your system, so if you do mess around with those partitions for whatever reason, you can't roll back from an update of some sort, or if something goes horribly wrong with your device, backups of those partitions can be nice to have.