Oomph's Targlet technology extends PDE's base functionality for specifying a target platform definition by providing a more expressive, flexible, and reliable mechanism.
Install Targlet Support
Use Help → Install New Software... and enter one of the update sites, e.g., http://download.eclipse.org/oomph/updates/milestone, into the Work with combo. Enter "Oomph Targlets" in the filter, and select the Oomph Targlets feature.
More documentation TBD.