OS X Build
Mac homebrew formula tap for maintaining a STABLE work environment for the OSGeo.org geospatial toolset. This includes formulae that may not be specifically for an OSGeo project, but do extend the toolset's functionality. To install OTB on mac you can follow the below instructions posted by Larry Shaffer on otb-users group
brew install osgeo/osgeo4mac/orfeo-40 -dv
This will build OTB 4.0 in debug and verbose mode. If you run into problems, please create and issue on the tracker. When creating an issue it is best to use the simple Homebrew troubleshooting command
brew gist-logs --config --doctor orfeo-40
Then, add the link to its output in the issue.