I have no idea - something post SP2 and pre SP3. Well I've set my computer up to download through the night before and this was the only time I installed updates and left it through the night so this was the only time this has happened. Unless you can suggest some other strange phenomenon for why the computer would restart, and why people would write articles on it automatically restarting such as
this, (to be fair though that article doesn't explicelty state which method of Automatic Updates they use (however I strongly suspect they have it set to automatically download and install)), either you're wrong, or my computer stuffed up and restarted itself. Hmm if only I hadn't reformatted since then I could've looked at the event log. Perhaps the article I read in the first place was actually referring to automatic download/install updates...bah oh well.