This release obviously aims to be what OS4.1.3 wasn't.
One of my goals is more frequent update releases. Update 4 is just another update and it does not imply Update 3 was bad or anything of the sort. AmigaOS will have an Update 5 out in the new year. Does this "obviously" imply Update 4 was a failure as well? Obviously not. Obvious when you think about it.