MorphOS does indeed run on the 1.42Ghz eMac. The Radeon 9600 driver is a little sluggish at present and there is no 3D but this should change with the release of MorphOS 3 or 3.1. Otherwise it's a solid (literally and figuratively) machine to run MorphOS on. However I would still recomend a mac mini 1.5Ghz if you can afford one.
MorphOS on eMac 1.42Ghz:
http://i593.photobucket.com/albums/tt11/Ruud-/Grab.png