Hildon is already packaged for Debian and Ubuntu (Ubuntu MID is using Hildon, also see johnx's beta2 release of Debian), it's just a matter of stitching everything together to get a nice, polished desktop environment like Nokia has done.

Of course you'll need to substitute in a lot of the stuff to replace Nokia closed-source UI-differentiation nonsense (various taskbar, statusbar, and home applets, etc.), but it gives you much better compatibility, and more versatility.

Take the good of Maemo without all the bad.