Later today, the development branch of Ark Linux will switch from glibc to eglibc.
We've been considering this move for quite some time, but being the small distro we are, we didn't want to risk breaking compatibility with others.
Now that Debian has decided to make the move, we can safely follow -- and still be the first RPM based distro with eglibc. ;)
The initial eglibc build in our repository will be from the 2.10 branch.