The new AmigaOS will be based on the ultra stable and effient QNX Neutrino kernel. I like it better than Linux. Check it for yourself at http://www.qnx.com The new OS will also support multiple processors like PowerPC and x86. Although the AmigaOS will be much more advanced (QNX and Amiga Inc. are working on this together)
So if it comes to stableness Linux and AmigaOS won`t differ that much. But when it comes to easiness to install and multimedia functions it will be superior.
By the way why do you guys think Atari is superior for use with music?? You can upgrade your Amiga with a 16 bit card and MIDI upgrade like every other computer platform. Maybe you just like the Software on Atari?? (Those can be ported you know, if there is a demand on the new/old Amiga platform) Technicly there just is no reason why it won`t be possible.
Sealance: Even the Old OS 3.1 can be very stable if you istall some patches. But I agree that some software written for it in the past is very unstable. (But blame the programmers for that!)