If you want to understand why I've made this change, go to this momentous post from Sunday and search the comments for contributions from me. I did not believe when I put that post up that I was about to end comments, but the comments — ironically, the comments insisting that I keep the comments — convinced me that I needed to let go of the blogging-with-comments game.
You can still comment on posts. You just have to send me email. Use this address. I'll presume you want to be quoted in an update to the post, but I'll be very selective about that. To see the first example of a post update with a quote from the email, go back to this post from yesterday.