I said back in April that I was going to be working on a second edition of the Typeclassopedia. Since then I have worked on it some, but mostly I’ve dithered trying to work out a toolchain for publishing it in multiple formats including PDF and (commentable) HTML. But it’s become increasingly clear to me that this is really just getting in the way of the important work of actually updating the content, and I ought to just choose a simple solution, imperfect though it may be, and get on with it.
In the meantime, it turns out that Henk Krauss (geheimdienst) has been doing the tedious work of porting the Typeclassopedia to the Haskell wiki (thanks!). It looks much nicer than I thought possible for a wiki page, allaying one particular misgiving I had about publishing in wiki format. And this format obviously makes it extremely easy for others to contribute.
The path forward is clear: I hereby declare that the Haskell wiki version of the Typeclassopedia is now the official version, and from now on I will be focusing my efforts there. You can expect a bunch of updates, improvements, and expansions over the next few months. If you have any improvements to suggest, you can make them directly, or leave a comment on the talk page.
blog :: Brent -> [String] 
Does this mean we should watch/subscribe to that page if we want to stay up to date with the future of the typeclassopedia, or will you announce a “finished” version 2?
I do plan to announce a “finished” version 2. Whether you want to watch/subscribe to the page is up to you.
That reminds me of Knuth being frustrated with the tools at hand for his Art Of Computer Programming book, and therefore procrastinating for years doing what eventually became TeX :)
That said, I found the Typeclassopedia absolutly enlightening, at a time I *needed* it to get started, and I’d love to see the second revision !
Indeed, I do that sort of thing all the time. (I procrastinated from writing a particular blog post for a year, and the result was diagrams. =) But I have to learn to pick my battles wisely. Glad you found the Typeclassopedia so helpful!
Your Typclassopedia was the first tutorial on Monads that really helped me to understand them, mostly because it explains all the steps between (Functors, Applicative etc.). Thank you so much!