For a long time I have been meaning to write this post. It was finally stimulated by seeing that the Electronic Structure Theory community has started an initiative to improve the Wikipedia articles relevant to their community.
I think most of the articles relevant to theoretical condensed matter physics and chemistry are quite poor or non-existent. We need to take responsibility for that.
I think the simplest way forward may be for us to encourage our graduate students to write and update articles for Wikipedia. Many draft literature reviews for undergrad, Masters, and Ph.D theses could be used as starting points. For that matter some of my blog posts, could be too. It could be quite educational for students to post material and hopefully see it revised.