We have laid a solid foundation for Darcheology, but it needs help to take it to the next level. Support for darcs 2, A Leopard interface that leverages core animation, peer to peer presence, querying and collaboration support on top of what darcs already has, and multi-core performance gains are all in the works, but waiting for time and talent.
If you love darcs, have a feel for human interfaces, and are proficient in Objective-C (or willing to learn ;-) why not consider helping out?