@lightweight Actually reading the article, it's a disaster - they call slack "free software" and make it clear they only have concerns about trivial technical issues like chat history and having to pay; "All things equal, we would certainly prefer an open source solution to a proprietary one."
They write "Slack is not open source" and "As an open source project, that should at least give us a pause to think if that’s really what we want." - refusing to even admit that what they were doing previously was totally unacceptable and was an affront to what a GNU package should be
It doesn't seem like they'll be ever leaving github unless github makes them leave.