Anybody with Windows Automatic Updates enabled should get a nagging message in the next 24hrs. It’s worth installing the new security patch asap, as the problem with animated cursors, of all things, is actively being exploited. It’s highly unlikely you’ll come across an infected website, but it can’t hurt to be safe. If you don’t have WAU enabled (and if not, why not?) you should head over to Windows Update and pick up the patch. Don’t be tempted by the ‘Microsoft Update’ option, though – it’s still evil.