OS4 isn't released, but...
*OS4 runs on the A4000/CSPPC (you probably knew that)
*Most of the modules that need to be PPC are PPC. Including massive re-writes like AmigaDOS (no more BCPL!)
*OS4 boots into workbench on the A1 - the drawback ATM is that graphics.library is running under emulation with some legacy chipset emulation - but it still works well enough to run programs stably
*OS4 on this CSPPC now seems in a very usable (ie perhaps getting close to releaseable???) state.
*Pagestream will be ported to OS4
*Photos of a prototype of the upcoming (next year) AmigaONE lite were released - this is a Mini-ITX board