The one thing I have noted that seems different to the earlier version (but perhaps I'm wrong in this) is that there is some kind of 'compacting' that goes on when saving a recording. It goes rather quickly though.
Perhaps this is the new version organizing old versions into the new formulation?
Regardless, I think all will like this upgrade.
Audacity 3.0
My LibriVox: https://librivox.org/sections/readers/13278