This was mentioned in the article, but if you're looking for a TogetherJS-like tool that takes a different approach to collaboration you should look at what we'

This was mentioned in the article, but if you're looking for a TogetherJS-like tool that takes a different approach to collaboration you should look at what we've put together at Firefly: http://usefirefly.com http://usefirefly.com. It works all the way back to IE 8 :)