For the development question regarding decentralized applications, the
lang-js hint would be sufficient in most cases, however, there are more than 700 questions tagged with solidity which could benefit a prettify plugin.
It would be great if someone can step up and create pull requests for the Ethereum programming languages directly at the google repository.
If we can get it included, we can request default syntax highlighing for Ethereum Stack Exchange.
See also, Syntax highlighting language hints.
Edit: If you think we need more languages added for Ethereum, comment below.