There are two big ones for Perl - Catalyst and Jifty. I would say Catalyst being the biggest and most advanced, while Jifty is right on the tail. Jifty focuses on the footsteps of Rails, with having an application set up right out of the box. Catalyst focuses more on the building blocks to building an MVC-based web app - you will have a basic site set up, but not all the CRUD right out of the box like you would Jifty. IMO Catalyst is the better because it is more flexible and builds from the very basics - you don't have all the fluff that you may not need with a basic Catalyst install. There are some CRUD set ups you can set up on top of Catalyst if you want to, though. Catalyst is also most stable, and has been around the longest. I actively use Catalyst on my GrandCentral Facebook App, and my SteepAndCheap SAC App for Facebook. I intend on using it to build quite a number of new sites as well.

As to the last release being November 2006, I wouldn't worry too much - there is still very much an active community supporting it. They recently had a bit of a re-structure, and are trying to decide the next phase to move it to, but they have definitely not given up. I hung out with the pump kings for Catalyst at YAPC::NA this year, and they have many plans for the future, including a book by Jon Rockaway to be released this fall. The book is also a reason for the lack of updates since November.

Let me know if you decide on Catalyst - there are a few others out there if you look around, but Jifty and Catalyst are the ones making the biggest strides in the Perl community.