After the release of KDE 4.3.4 for Linux, it is now available for Windows as well. The development of KDE for the Windows platform is done by the KDE Windows Team.
The release includes Qt 4.6, KOffice 2.1.0, Konversation 1.2.1 and KTorrent 3.3.1 in addition to the other packages from SC 4.3. The installer can be downloade from here. However, the KDE softwares in Windows are still in development and not considered suitable for day to day use.