Fedora 12 includes the haskell-platform-2009.2.0.2. Haskell Platform is standard set of libraries and tools which provide a stable known platform for developing Haskell projects.
ghc has been updated to 6.10.4. The xmonad window manager and quite a few more libraries have also been added (cgi, editline, fgl, GLUT, haskell-platform, network, OpenGL, tar, time, utf8-string, X11-xft, xmonad, xmonad-contrib).
ghc-rpm-macros contains the rpm macros used in the Haskell Packaging Guidelines.