"The functionality change to Autorun is, for the moment, marked as Optional for Windows XP. Users who have automatic updates set to install both Optional and Important updates have already begun to receive the update. We plan over the next few weeks to re-set the change to Important, allowing it to reach the remainder of the Automatic Update-using XP community."
"Microsoft says that this was a miscommunication and not a mistake."
And so AutoRun lives on, and even after Microsoft adjusts the update from optional to important for Windows XP, update KB971029 only limits non-optical media functionality.
So… to limit AutoRun, manually run Microsoft Updates. To completely kill AutoRun, click here and use the "fix it for me" option.