PostGIS 2.0.0 windows binaries are up http://www.postgis.org/download/windows/#windbinaries. This is the first ever version of PostGIS to support PostgreSQL 64-bit windows installs. We want to extend a big thank you again to our generous sponsors for helping make this a reality.
We are in the middle of packaging the installers for both windows 32-bit and 64-bit installs and hope to have those up in the coming weeks for those who require that comforting Setup button. They will then be available via StackBuilder.