You can grab it from:
It has a bunch of bug fixes – most notable mentions include:
- Improved performance for XP SP2 as a guest
- Bug fixes for running on Athlon and Prescott processors
- You can now use DOS Folder Sharing and EMM386 at the same time (yay!)
Plus a whole bunch of other goodness.
There have been a small number of reports of problems installing the upgrade though (bummer) – but they all seem to be resolved by uninstalling and reinstalling.