You want to talk with mst for Catalyst (as the lead dev) and for general knowledge. audreyt is a primary author of Jifty along with Jesse Vincent. Jesse Erlbaum is the lead dev for Cgiapp, but Mark Stosberg does a lot of the release work. Every one of them has been very easy to approach.

Personally, I've used Cgiapp and Catalyst. I've written quite a bit on Cgiapp on this site which you can find - a lot is from at least 3 years ago when I was using it more actively and contributed to it (some of the error-handling).

For my sense, Cgiapp is better for smaller sites - it has less of a learning curve and is easier to deploy. Catalyst is much more heavy duty - it takes a bit more learning and requires thinking more in Cat-terms. But, it scales extremely well, has great support, and interfaces with a ton of different modules out of the box or though an extensive plugin system. All the frameworks have a plugin system, but Cat's is built into the entire framework vs. being an afterthough as Cgiapp's was.