The question of IRC vs. Email list is only on the surface a culture clash. But below, it's the
difference between people who can work full-time on a project (or are, at least, full-time
reachable for communication on a project) and people who do so in their spare time. Since more
and more people can afford to make a living out of Open Source software, the first class of
contributors gets larger.
Now, these full-time contributors have already a big advantage when it comes to shape a
project; not only code-wise, but also in architectural and design decisions. This is already
visible on mailing lists, where some people can always respond within the hour (and thus shape
the future discussion) and others answer that evening or the following day. Moving
communication to IRC as some ``standard'' communication medium that's expected leaves those in
the cold who can work only in the evening (or live in other parts of the world and not just in
another US time zone, but ESR seems to be oblivious to that point). And, as noted already, to
read up such discussions later, is much harder with IRC than with email.
Moving day-to-day communication to IRC has the effect of building a cabal for a project, it
forwards the creation of an `inner circle', loosing the bazaar effect that ESR says is so
important. That said, IRC is a very good medium to have project meetings at preset times, to
discuss things that would take too long over email.
For me, the difference boils down to the questions: ``Are main developers expected to be on
IRC the whole day through?'' vs. ``Why don't we use IRC as an additional communication medium
for project meetings?'' The first is bad, the second is good.
PS: I'm the CEO of a small consulting company. My staff can spent 20% of their time on Open
Source projects of their choosing. But I would not allow them to be on IRC full-time for the
rest of their working time; after all they have projects to do that bring in the money for
those 20% free work.