Re: address@hidden: [patch] factor out comment-or-uncomment feature from comment-dwim]

[Richard Stallman]

    This is a significant deviation from the old behaviour of C-u C-SPC,
    but the new functionality is much easier to use...!

I think it is good, but I think we should also look at the idea
of changing C-x C-x in a similar way:
doing it twice would temporarily enable transient-mark-mode.