All of these Wikipedia browsers miss a very important point: A web page is not a book. Wikipedia "pages" already suffer from skeuomorphism: the presentation of data reflects offline materials to the point where the online functionality is compromised. "Pages", "articles", "page turning", lists of "references" are not well-suited for the web. More about Wikipedia's UX issues here: http://newslines.org/blog/wikipedias-13-deadly-sins/