"GNU D Compiler (GDC) for Mac OS X" :
http://sourceforge.net/projects/gdcmac/
currently just a RPM build of vanilla GDC

A packaged installation for Mac OS X 10.3
"Panther", of the latest version of GDC,
GDC 0.10 - which corresponds to DMD 0.110

Installation disk image with packages:
 29M    GDC-0.10-6.dmg
(also includes the C and C++ compilers)

It will install under /opt/gdc, and there's a
custom patch for UTF-8 comments check applied.
The main GCC version being used is GCC 3.4.3.

Eventually there will be more Mac-specific
patches, such as support for -framework and
-mcpu=G4 and pascal strings and similar things.

The GDC home page can be found at:
http://home.earthlink.net/~dvdfrdmn/d/
D was ported to GCC by David Friedman.

--anders

PS. Here's the stylish installer disk image:
http://sourceforge.net/project/screenshots.php?group_id=135857