As typical, it may be wiser to wait for 14.1.1 than charge full speed into upgrading to 14.1.0. Then again, at least on Mac one can have multiple versions installed easily...
Only significant problem I've spotted, though, is that ContourPlot renders poorly on my MacBook Pro. Then there are documented new features that don't actually work...
IMPORTANT: Mathematica, Wolfram|One, and other products are now accessed via the new unified product WOLFRAM https://community.wolfram.com/groups/-/m/t/3238233