I am not saying that there can't be valid reasons for hating Java. I just think most of the times it is rather the specific frameworks than the language itself that pisses people off. For example I can't bring myself to write EJBs - having to create 5 files just to be able to call a method remotely exceeds my pain tolerance. Yet in many big cooperations someone up in the management chain has decided that every Java Application has to use EJBs. That I hate, too. It's misleading to judge Java based on that perversity, though - EJBs are just a framework written in Java, not the Java programming language.
Anyway, out of curiosity, is Perl still relevant today? Why would people choose Perl over Python or Ruby?
From your description it sounds like you were frustrated by coding horrendous Perl and instead of learning it you moved to a language with training wheels. I'd rather just fall a few times while I'm learning so I can go much faster afterwards.
"Why would people choose Perl over Python or Ruby?"
It's fast in productivity and performance. There are great books. It's on every Unix machine. CPAN still reigns supreme as the ultimate library repository. These days there's some great frameworks for web development, my favorite being Catalyst with DBIx::Class and Template Toolkit.
Ruby is mostly just Perl without all the mental baggage of people seeing bad Perl code for years. The way a restaurant might avoid saying "squid" and instead say "calimari" -- it sells a lot better.
Also whenever I take on a new programming contract, I just start the computer the company provides me with, download the Java documentation and off we go.
Fad paradigms: no, but I know that if I need something, someone has already written a framework for it.
You're moving from a verbose, bloated, over-engineered system to a terse and simple system. I think you're looking for something that doesn't exist because it's not how Ruby programmers work -- they use a language small enough to actually keep in your head and that's a huge part of the productivity to be had.
My ride with RoR hasn't been smooth so far. Far from having my first web app running within minutes. Instant Rails didn't work at all, and I spent hours trying to find a database driver for MySQL for Ruby. It's all very confusing. I suspect there is already a database driver bundled with RoR, but how would I know (documentation, where are you)? Googling only led me to some strange page where you could compile your own driver from C source code (and with what compiler, if I am on windows), which presumably was in some kind of alpha stage.
At least with Java I know that there usually exists a stable and proven solution... The training wheel analogy was maybe not so bad at all: Java applications just tend to be more stable than the scripting stuff. And other than bikes with training wheels in the real life, Java is also faster.
"But I have the impression that many people who bash Java don't really know it."
Interesting complaint from someone who just bashed Perl and almost certainly doesn't know it well.