Thanks to the efforts of a number of folks (Tim Sutton, Stephan Holl, Radim Blazek) we have a Linux chroot for cross compiling the Windows version of QGIS. This provides a complete development environment for building QGIS and its dependencies using the MinGW compiler chain on Linux. Currently this is the only functional way to build QGIS on Windows with the GPL version of Qt. If you are interested in using the chroot, you can download it at: http://download.qgis.org/mingw_chroot.tar.bz2 (374Mb).

Obviously you only want to download this if you intend to develop and/or compile QGIS for Windows. Since binary distributions for Windows are available there is no need to compile it if you just want to run QGIS "out of the box".

Information on using the chroot can be found on the QGIS Wiki at: http://wiki.qgis.org/qgiswiki/BuildingWindowsBinaryOnLinux

If you are interested in developing a native build environment for QGIS on Win32 (MinGW, Qt/Windows Open Source Edition), please let us know. We would like to provide both the cross compiler and native environments for building QGIS on Windows.