@Nate:"I am still waiting for someone to actually point out a technical area where OS4 has a clearly superior point"
I don't think you'll get such a response from any technical person. But you should have plenty of non-technical people leap up with "points".
Frankly, I don't think it's possible to compare them. Perhaps if you drew up a large spreadsheet, you could assign weightings to the pros and cons of each, and work out a score, but no one would agree with it.
MorphOS has been designed from the ground up to be compatible with old AmigaOS APIs. Presumably some extensions have been added that are incompatible with the old APIs.
OS4 is a re-write of the old code that MorphOS was designed to be compatible with. Certainly extensions have been added that make new code incompatible with the old APIs.
Some of it has been completely re-written and is as modern (or more so) than the corresponding MorphOS feature. Some is just a re-compile of old 68k code for PPC, and the rest is somewhere in between. Oh, and there are some bits that exist only in 68k binary form and have to be emulated (eg ARexx). I don't know where they fit in the spectrum, but MorphOS probably has the same problem.
tony