Hmmm, ran that link and no luck. One of my three PC's thinks that daylight saving ended this weekend. Also tried running a Microsoft "cumulative Dec 2008" patch for DST issues (KB 955839), but wouldn't let me because it said the patch was already installed (probably the one above).
My time zone is definitely set to Sydney and I have rebooted a couple of times and sychronised the time with the Windows website, but it still thinks daylight saving has finished. Unless anyone has any great ideas, I think I will just leave it for a week until the rest of NSW catches up with my errant PC! - all the Guide times are an hour early too, so I shouldn't miss any shows.