Earlier quoted context omitted.
Genuine question -- how how is it been a revelation? It seems to be very similar to HipChat, which was just an iteration on previous chat systems.
Hipchat is awful and Slack is phenomenal. I mean I know that probably isn't what you want to hear but it's so hard to describe it any other way. UX/integrations/apps/speed/etc might all be the answer but it was visceral for me.
If I have to cycle through 4 rooms to get to the conversation I want, it can take seconds just to Option+UpArrow there.
Plus I can't manually reorder rooms as I like. I don't get why everyone talks about the Slack UX. Slack has snippets. Which I find mostly useless. Especially since they kill performance. But HipChat lets you reorder rooms as you see fit. Which is something I actually used and miss desperately.
At least Slack has finally gotten rid of the useless Channel vs Group distinction?