Amarok 2 definitely works not at ~x86 only. Reproducible: Always Steps to Reproduce:
If you want to have more arches added, please tell which one. And I hope you were testing amarok-2 on all those arches you want to have added.
It should work on platforms on which KDE, Qt, Phonon, xine-lib, mysql and other Amarok's dependences works. At least Amarok works on ~amd64, been manually built from sources (without emerge).
Bug #238487 is blocking amarok 2 on amd64 at least.
Let's wait until bug #238487 gets finally fixed.