What Does This Mean for You?
Beta releases are a way for you to get a sneak peek at WordPress updates that are still in the development phase. WordPress warns that these releases are unstable and should not be used on important sites. Simply run on a production site and learn about all the exciting new features before applying to your site.
Beta updates are very valuable to you as a user because not only do you get to practice with the updates, but you get to make your own recommendations as well. You can help WordPress by providing feedback and helping to find as many bugs as possible.
What to Expect
With this new update, you will be able to identify problems on your dashboard. WordPress will catch and stop the problem code once identified. In April 2019, WordPress is increasing the minimum supported PHP to 5.6. WordPress 5.1 will show you warning signs and help upgrade your version of PHP if you are not prepared for this update. There are many perks for developers as well, like the Cron system which can now be more easily replaced with a custom cron handler.