Game Blender previews are coming again. Don't worry if things don't work: this release might have issue due to upgrade to Bullet 2.x.
Malachy Duffin works on some patches and other bugfixes, and those fixes will be included in upcoming previews. See also http://blenderartists.org/forum/showthread.php?t=81102
Blender 2.43 Preview 6 download for Win32:
http://www.continuousphysics.com/ftp/pu ... -win32.zip
Blender 2.43 Preview 6 download for Mac OS X i386:
http://www.continuousphysics.com/ftp/pu ... -Xi386.zip
Rigidbody Constraint editing sample .blend
http://www.continuousphysics.com/ftp/pu ... .blend.zip

Erwin