What language/system to use for a web page translator?

I need to write a small system that might be called a web page translator. It processes web requests by fetching pages from another site, scraping data from them, and reformatting the results in a more suitable form. What language or system should I use to implement it?

The system will be useful to me personally, and probably to a small community of other users. A hundred regular users would be a lot.

I could implement the system using any number of app engines, and I have experience with a number of languages: Java, C++, Python, Javascript, Go, and Haskell. Haskell and Yesod are appealing because I like the rigor of the language. But Haskell skills are rare, and I want to make it easy for other users to contribute to the project, which suggests I should use a more common language, like Python. Micro-frameworks like Flask are appealing in their simplicity, but might be a bit underpowered, which get me to Django.

So, thoughts?