Well, even though grass-64 was built, the installation of grass-70 failed:
GRASS GIS 7.0.0beta2 compilation log
--------------------------------------------------
Started compilation: Wed Jul 2 10:08:13 CEST 2014
--
Errors in:
/private/tmp/grass-70-KxEP/grass-7.0.0beta2/gui/wxpython/rlisetup
/private/tmp/grass-70-KxEP/grass-7.0.0beta2/gui/wxpython/mapswipe
/private/tmp/grass-70-KxEP/grass-7.0.0beta2/gui/wxpython/gmodeler
/private/tmp/grass-70-KxEP/grass-7.0.0beta2/gui/wxpython/dbmgr
/private/tmp/grass-70-KxEP/grass-7.0.0beta2/gui/wxpython/psmap
/private/tmp/grass-70-KxEP/grass-7.0.0beta2/gui/wxpython/animation
/private/tmp/grass-70-KxEP/grass-7.0.0beta2/gui/wxpython/vdigit
/private/tmp/grass-70-KxEP/grass-7.0.0beta2/gui/wxpython/iclass
/private/tmp/grass-70-KxEP/grass-7.0.0beta2/gui/wxpython/timeline
/private/tmp/grass-70-KxEP/grass-7.0.0beta2/gui/wxpython/gcp
--
In case of errors please change into the directory with error and run 'make'.
If you get multiple errors, you need to deal with them in the order they
appear in the error log. If you get an error building a library, you will
also get errors from anything which uses the library.
--
Finished compilation: Wed Jul 2 10:10:06 CEST 2014
make: *** [default] Error 1
==> Formula
Tap: osgeo/homebrew-osgeo4mac
Path: /usr/local/Library/Taps/osgeo/homebrew-osgeo4mac/Formula/grass-70.rb
==> Configuration
HOMEBREW_VERSION: 0.9.5
HEAD: 4d99912ef69e44480cca22a3170a8171d0f4f681
CPU: 8-core 64-bit haswell
OS X: 10.9.3-x86_64
Xcode: 5.1.1
CLT: 5.1.0.0.1.1396320587
X11: 2.7.6 => /opt/X11
==> ENV
HOMEBREW_CC: clang
HOMEBREW_CXX: clang++
MAKEFLAGS: -j8
CMAKE_PREFIX_PATH: /usr/local/opt/gettext:/usr/local/opt/readline:/usr/local/opt/sqlite:/usr/local/opt/libxml2:/usr/local/opt/liblwgeom:/usr/local/opt/ossp-uuid:/usr/local/opt/openssl:/usr/local/opt/libffi:/usr/local
CMAKE_INCLUDE_PATH: /opt/X11/include:/opt/X11/include/freetype2:/System/Library/Frameworks/OpenGL.framework/Versions/Current/Headers
CMAKE_LIBRARY_PATH: /opt/X11/lib:/System/Library/Frameworks/OpenGL.framework/Versions/Current/Libraries
PKG_CONFIG_PATH: /usr/local/opt/libpng/lib/pkgconfig:/usr/local/opt/libtiff/lib/pkgconfig:/usr/local/opt/proj/lib/pkgconfig:/usr/local/opt/sqlite/lib/pkgconfig:/usr/local/opt/freexl/lib/pkgconfig:/usr/local/opt/libxml2/lib/pkgconfig:/usr/local/opt/json-c/lib/pkgconfig:/usr/local/opt/libspatialite/lib/pkgconfig:/usr/local/opt/ossp-uuid/lib/pkgconfig:/usr/local/opt/openssl/lib/pkgconfig:/usr/local/opt/postgresql/lib/pkgconfig:/usr/local/opt/gdal/lib/pkgconfig:/usr/local/opt/fftw/lib/pkgconfig:/usr/local/opt/freetype/lib/pkgconfig:/usr/local/opt/fontconfig/lib/pkgconfig:/usr/local/opt/pixman/lib/pkgconfig:/usr/local/opt/libffi/lib/pkgconfig:/usr/local/opt/glib/lib/pkgconfig:/usr/local/opt/cairo/lib/pkgconfig
PKG_CONFIG_LIBDIR: /usr/lib/pkgconfig:/usr/local/Library/ENV/pkgconfig/10.9:/opt/X11/lib/pkgconfig:/opt/X11/share/pkgconfig
ACLOCAL_PATH: /usr/local/opt/gettext/share/aclocal:/usr/local/opt/libxml2/share/aclocal:/usr/local/share/aclocal:/opt/X11/share/aclocal
PATH: /usr/local/Library/ENV/4.3:/usr/local/opt/pkg-config/bin:/usr/local/opt/gettext/bin:/usr/local/opt/libpng/bin:/usr/local/opt/jpeg/bin:/usr/local/opt/giflib/bin:/usr/local/opt/libtiff/bin:/usr/local/opt/proj/bin:/usr/local/opt/libgeotiff/bin:/usr/local/opt/geos/bin:/usr/local/opt/sqlite/bin:/usr/local/opt/libxml2/bin:/usr/local/opt/ossp-uuid/bin:/usr/local/opt/openssl/bin:/usr/local/opt/postgresql/bin:/usr/local/opt/gdal/bin:/usr/local/opt/unixodbc/bin:/usr/local/opt/fftw/bin:/usr/local/opt/wxmac/bin:/usr/local/opt/freetype/bin:/usr/local/opt/fontconfig/bin:/usr/local/opt/glib/bin:/usr/local/opt/cairo/bin:/opt/X11/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin
Well, even though grass-64 was built, the installation of grass-70 failed: