Version 4.2.1 is a maintenance release designed to make your daily work easier. You won’t see a redesigned dashboard, but you will notice things just work better.
A: No. It is a patch release (indicated by the third number ".1"). It contains only bug fixes and minor performance enhancements over version 4.2.0. There are no new features or breaking changes to the user interface.
No new learning curve. Just a smoother experience.