I've been using WLW in Beta for a while now and have loved it. I saw that it recently moved out of Beta and was keen to upgrade. If you download the installer from here, like I did you may have found that it complained about not being supported on Win2K3 - bummer I thought.
A little digging around and I found that if you can access the MSI directly it will install OK. So to save you some time here's s link to a page with links to the MSI.