Hi Ben and thanks for hunting us!
The short answer is that workgroup is a much simpler/faster/less noisy platform - it actually has no teams and no setsup, you simply open workgroups on-demand, in seconds, with anyone you want, from any company, to discuss any subject.
So if Slack is ideal for a dev team working mostly internally, Workgroup is perfect for anyone working with people from inside and outside their company, especially when working with non-tech people, who find Slack a bit much. This includes business people, investors, service agencies (from lawyers to PR agents), freelancers - and anyone who would find themselves switching between 10 teams.
The longer answer, since I've been asked this already, is in a post I wrote, called: "Is Slack the last business app we’ll ever need?" https://medium.com/@amibendavid/...
The reason we built Workgroup is that in our vision, practically every email conversation with people on CC, represents a group of people trying to get things done - a workgroup, and can achieve huge efficiency advantages from switching the discussion to simple real-time messaging platform.
So since even the most die hard Slack fans (including the CEO), still connect outside via Email, I think most Slack users will find it very useful to open on-demand workgroups outside their teams.
Would love to hear your thoughts and feedback...
@amibendavid You just described all the weakness of Slack and the strengths of Skype. Additionally Skype most likely has the person you want to chat with signed up.
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