PlanetLab is in the early stages of federation. This means forking off autonomous authorities that are responsible for a subset of the global slices and nodes. These authorities will then peer with each other to build a federated system.
This effort is being done with an eye towards eventual federation across a collection of testbeds, including GENI. For an overview of the architecture (preliminary draft form), see Federating Slice-Based Network Substrates. PlanetLab is not totally consistent with this architecture, but we are evolving it in this direction.
We are currently conducting a federation trial with the OneLab project, which is creating independent slice and management authorities spanning Europe. Read the Federation Roadmap to get a sense of how this trial will unfold. Click here to see the set of nodes currently running under the PlanetLab-Europe banner.