You can flash the same way as the the flash images of Maemo, however you have to prepare a flash image yourself because it contains some parts which are not officially distributable. Here you can find some instructions:

http://dev.openbossa.org/trac/mamona.../RunningMamona

You can also try some of the precompiled rootfs-only images but sound is not supported with them and I don't know how they can be installed.

I've just tried Mamona and I think from developers point of view it is very promising. From users perspective however it is not yet very usable. The interface seems somewhat slower than Maemo and (to me) it seems optimized for devices with larger screen.