I think is is a good list to start on. . .
http://www.tiobe.com/tpci.htm

Personally, out of the top 20, I'd say any of the following would be "well suited" to web programming. The main qualifier would be whether or not you actually like it:

• Serverside Javascript (this is something I've been dying to try lately)
• Visual Basic
• C#
• Ruby
• Perl
• Python
• D (I still want to write a webapp in D)
• Java - will be "on the table" for years to come
• Lisp, if that's "your thing". Reddit is a proof-of-concept IMO. There's even screencasts on how they developed it.
• Lua - An up and comer. Don't know if many have used it on the web yet, but I could be pretty certain that there are some applications

Maybe I should clarify that I'm really interested in what languages are "well suited" to web programming (bearing in mind that a framework may make a language "well suited").

I think there are tons, and potentially more every day.

Personally, I'm of the opinion that there really isn't /that/ much going on in these frameworks. A sufficiently large project will have the time budget to allow for writing your own custom framework with your needs in mind. With this in mind, the question really boils down to what actual language you want to be working in.

As for the actual existing frameworks, a few things real quick:

• A google search for "perl mvc framework" turned up a lot, with the most popular result being 'catalyst', whose home page at least looks well polished.
• There are literally dozens of mvc frameworks for python. I think django gets the attention because it has done all it can to be a rails copycat and ride the wave of publicity.
• Being in "the ruby circle", I read about new ruby frameworks all the time; some of which pick and choose components from rails, and some who don't. In the portland area, the die hard ruby guys despise rails, so they've all moved on to other frameworks.
• PHP also has symfony. I've watched the screencast; they do have a lot of code written, but I'm scared to see it.
• I think the most important thing to remember is the Java frameworks. Struts was given to Apache in 2000, and by my informal survey, they were the first to the party.
• Seaside: having done a brief look into it, I hesitate to put it into this discussion. It feels more academic than actually useful. That said, I know nothing about it, and nothing about its hosting requirements.
• Also, with the Mono project, I think you're open to the .NET framework, which is actually pretty solid. In particular, MonoRail is a rails clone that runs on the platform.

My bottom line is that you should use a language that you and your company/client is comfortable with, and one that you know you can host solidly. Getting a framework in place is just a matter of some porting.

And a final note: doing a brief bit of looking on wikipedia, they have the entire list. So . . . no idea why I just typed all that up :)

http://en.wikipedia.org/wiki/List_of_web_application_frameworks