Personally speaking, I am very glad they made the move. It is clear what Satoshi's intentions were, that isn't debatable. The 1MB folk can have an altcoin that continues their vision. To date, people signing onto bitcoin were signing onto a vision that was plainly laid out by Satoshi. Of course, any alternates are fine, but only in addition to the one that has been described in the white paper, and shared by so many enthusiasts.
Email on the bitcoin developer list from Satoshi (maybe?) on the fork: http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-August/010238.html
According to some on the now deleted HN discussion it is (rephrase:) the email contains the correct headers. I have no idea. Here's the Bitcoin XT site: https://bitcoinxt.software/