Language biases
I've found I can only really be excellent at one language at a time. I use a bunch, but I'm always most proficient in Java. My goto (see what I did there?) language used to be C++, but it was eclipsed by Java sometime during my freshman year in college. At any given moment I'm in the process of completely forgetting how to code a single line of one language while becoming much better with another one. The exception being Java which I can always put down for months and come back and be just as good with it as ever. I think it's mostly the nature of dual booting and writing code for *NIX and Windows. I use Java on both, but on Windows at work I use VBA (ugh!) and promptly forget the language when I haven't used it in a month or two. At work on the *NIX side, I write a lot of bash scripts, but not enough that I've ever formally learned the language, since I'm never using it on Windows under Cygwin.
At any rate, IMHO, you should probably become very skilled in a single language and be able to pick up others as you need. I've found that I like C/C++/Java syntax and I gravitate towards that family of languages. That being said, you should be familiar with many types of languages and their paradigms. Not that you'll ever write something in Haskell, but messing with a functional language can be fun and make you think differently about how you use your favorite language.
P.S. - addressing Speakerphone Dude's listing. Not sure if you're trolling or not, but I think these days Python is considered a Web server side language due to the Django framework. I think that's mostly where it's finding its niche. Granted, Red Hat uses it for everything (GUIs included), but I don't think many people use it merely for scripting. Correct me if I'm wrong.