"MorphOS 1.0 (for AmigaOS 4.0 no details available)"
Copy from the Requirements page. There will be AOS4 version, when it will be available.
This blind hate towards MOS is what will kill it. Just as it killed PUP. Well, now it turns out, a few features of PUP were better and will be used in both MOS/AOS4 (gcc compiler, elf format, scheduler etc.)
Now that's why I say OS4 will be superior. Never the less, I'm going to buy it for MOS, but I have no illusions. :-)