So now that Dynamics 365 Business Central is live, then I'm sure that you have gotten a peak.
Either via one of the many blog posts, webinar or videos on YouTube. There is already so much documentation about Business Central. Most of it also already available for NAV 2018, or will be when NAV "on-premise" also becomes Business Central in Fall 2018.
The team from Microsoft Development Center Copenhagen in Denmark has made this little video about their favorite features of Dynamics 365 Business Central.
These are just a few of the features mentioned in the video. Please reply if you have other features which should be included on the list?