Statamic 6 has officially entered beta. After an extended alpha phase with 21 releases, the team is confident in the stability and expects a short beta period before the stable release.
Statamic v6 features

The update includes a completely redesigned control panel, built-in two-factor authentication, a command palette for keyboard-driven navigation, and a move to Vue 3. The team describes it as "the most significant update" in Statamic's history. Checkout the Statamic 6 Sneak Peek for all the details.
To upgrade, update your composer.json to specify "statamic/cms": "^6.0" and run composer update. An upgrade guide is available for those transitioning from version 5.
For the full list of features and changes, check out the Statamic 6 Beta announcement.