The difference is that with Slack you usually have some sort of common bond with the other people there, in terms of being either members of the same organizati

The difference is that with Slack you usually have some sort of common bond with the other people there, in terms of being either members of the same organization or else mutual alumni of some organization. Because of that it's not immediately obvious that Slack should be no different than just asking a Linux question in some random FreeNode channel or whatever. That's actually a pretty big issue that doesn't bode well for the longterm viability of Slack, if (for example) it turns out that it leads to significantly worse organizational decision-making than email due to lower participation rates.