Wikipedia Signpost/2012-01-30/Technology report

Of course, the introduction of a programming language would bring with it a number of other problems, particularly with regards to privacy, security and memory footprint. As a result, the long term consensus was that the introduction of a programming language would be a major undertaking, including time for discussing which languages would work best in a heavily sanitised environment. The project as a whole has been discussed at regular intervals, but it was only this week that a consensus seemed to emerge in favour of Lua, a lightweight but relatively unheard-of language generally regarded as being "easy to learn"