WordPress 5.0 released today (https://wordpress.org/news/2018/12/bebo/) and the big question is…should you update now or wait? There have been others providing advice: https://xomisse.com/blog/wordpress-gutenberg/.
Here is my take:
If you are using a recent WordPress theme (within the last couple of years) and you have kept your plugins updated…you are probably OK to upgrade to 5.0.
If you have an old theme or one that has been modified from the original or a custom theme…I would wait until after the beginning of the year. Let a few updates happen and then look to upgrade.
ALWAYS back up your WordPress website before you upgrade…just in case. I am a fan of the plugin (All-In-One WP Migration) for backups…it is simple to use and simple to restore a backup if needed.
I have begun updating some sites….so far so good (as you can see in the photo above). I probably wont get them all (about 70 to do overall) updated until very late in the year (sometime after Christmas).
I have been monitoring social media and I am not seeing people flip out at this point…meaning many are waiting or few problems happening in the WordPress community based on this update.
Good luck to you all.