I gave a presentation comparing MVC frameworks a few years ago. You can read the slides and look at the code samples. However, these do not include Jifty.

In general, the difference you'll notice between Jifty and Catalyst is that Jifty has a defined set of tools and way of doing things while Catalyst tries to more hands-off. If you want a more integrated framework that gives you more guidance on how to do things, Jifty might be a good choice. If you already have tools you want to use (a templating tool, an ORM, a form validator), you will probably prefer Catalyst.