David E. Wheeler has done some great work with PGXN. It's an excellent example of how you can build something CPAN-like without being weighed down with design decisions from long ago. There's JSON all over the place and there are mashups just waiting to happen.
May 2011 Archives
Lots of exciting things have happened with MetaCPAN since I posted the last update. The most important development was the announcement that Moritz Onken's Google Summer of Code proposal for MetaCPAN was accepted. Moritz had already made a huge impact on MetaCPAN before his proposal was accepted and this gives him even more time to devote to improving both the front and back end of MetaCPAN.
I've always thought of this project as a marathon rather than a sprint…