To make a (probably) long story short ...
Yes, MorphOS will officially support Sam460 at some point. It still needs some work on drivers but I have shown a working version booting at Pianeta Amiga Italy.
This is unrelated to the ongoing work on MorphOS 3.2, though.
Our main focus is R300 3D drivers and PMacG5 support for that one and maybe some other enhancements we can't disclose yet.