Microsoft releases Windows XP SP3 RC2
You'll need to run a script that will add a key to your Windows registry allowing you to download SP3 RC2. This is still pre-release software, so Microsoft isn't going to be pushing it on all Windows XP users just yet.
Microsoft has also posted the release notes for RC2, so you can read the long and mostly boring list of changes. There are a few new features under the hood, like "better black hole router detection," and "more descriptive text to explain the settings," but for the most part there's nothing to write home about. If you like to have the latest and greatest installed on your system at all times, you might want to check out XP SP3 RC2. If you'd rather have a stable system running software that's been well tested over the last few years, you might want to hold off for a while.