I thought Eclipse was great for Java, but so far I haven't been to happy with it for anything else. For Perl development (and PHP, when forced to touch that stuff) I use, as you mentioned, vim with an assortment of command line utilities (mainly sed, grep, and awk).

So far I haven't found a compelling reason to try an IDE, so I don't know if there's any great new features I'm missing. I'm betting the IDEs have features that will do everything I need, but I just don't want to take the time to learn how to use them. Plus there's the advantage of being able to log on to any Unix/Linux machine anywhere and be able to start developing without worrying about getting your preferred tool installed, or learning to use an alternate.

I would like to find a nice VisualStudio.net style IDE with a Drag'n'drop GUI creator (for Perl or Java, or any language for that matter), but I haven't yet. But, as I'm writing this, I have ZooZ installing, so hopefully that'll work well.

EDIT: ZooZ is pretty awesome :)