I used Microsoft Visual C++ 2008 to make this release of the RMagick gem for Win32. This change is required for compatibility with ImageMagick. However, there is some question as to whether Visual C++ 2008 is compatible with the Ruby 1.8.6 One-Click Installer. My tests ran successfully but please evaluate this version carefully and report any compatibility problems in the RMagick Help forum.
For a summary of the RMagick 2.9.0 changes, see this news item: http://rubyforge.org/forum/forum.php?forum_id=29713