The Twin Cities will have a new user group focusing on programming languages. You can get all of the details at the TCLUG website. Their explanation is as good as any I could come up with...
As developers, we use a number of languages throughout the lifecycle of a project and our careers in general. Learning core aspects and features from other langauges can help a developer apply new techniques and designs to their own projects. This group is open to anyone who has a deep appreciation for programming languages and all of their related topics (compilation, parsing, execution, syntax, etc.). Talks are not limited to any OS or VM (or lack thereof). If you want to talk about Ruby, F#, Lisp, etc., stop on by!