I must say I am quite impressed with that achievement. On the other hand, RiscOS is presenting itself as a sort-of-vague-Unix to that program, and that makes porting things a helluvalot easier. All the nasty bits are handled by RiscOS's UnixLib linker library---that's the infamous ixemul.library to Amigans. Nevertheless, keep in mind it has taken years of committed efforts of a small group of people, and that is just to get glibc and X11 going! That is completely comparable to creating AmigaOS4 or AROS.
Amizilla is trying to make it all native, but progress is exceedingly slow (people on the mailing list often excuse themselves for not having worked on stuff a great deal), and some of the problems they were facing just made me cringe with their complexity. There was one topic suggesting that a sort-of source scanner be built to transform every gtk/glib-call into a matching MUI/Intuition-one: the libraries just handle things so differently. You have my sympathies.
In any case, you can watch progress yourself on the mailing list: it lives on Yahoo! Groups. Don't be all excited, however: message traffic is thin, on average slightly more than one message a day, sometimes a little more when diffs to the NSPR are posted.
