So I'll reiterate my invite to anyone interested in actively hacking on Fedora on ARM -- drop us a line @ devel@lists.laptop.org or at the Fedora ARM list.
One of the stepping-stones in the Fedora process was a F14 build for armv5tel, and OLPC will soon be shipping XOs with a F14-based OS.
That's just our initial OS, which unfortunately doesn't make full use of the silicon.
We plan to switch to a subsequent build that targets armv7hl (perhaps F17). Quite a bit of fun hacking will be required before its "children-ready".