  The Gemini Planet Imager (GPI) is currently in its final Acceptance & Testing
stages. GPI is an XAO system based on a tweeter & woofer architecture (43 & 9
actuators respectively across the pupil), with the tweeter being a Boston
Michromachines $64^2$ MEMS device. The XAO AO system is tightly integrated with
a Lyot apodizing coronagraph. Acceptance testing started in February 2013 at
the University of California, Santa Cruz. A conclusive acceptance review was
held in July 2013 and the instrument was found ready for shipment to the Gemini
South telescope on Cerro Pachon, Chile. Commissioning at the telescope will
take place by the end of 2013, matching the summer window of the southern
hemisphere. According to current estimates the 3 year planet finding campaign
(890 allocated hours) might discover, image, and spectroscopically analyze 20
to 40 new exo-planets. Final acceptance testing of the integrated instrument
can always bring up surprises when using cold chamber and flexure rig
installations. The latest developments are reported. Also, we will give an
overview of GPI's lab performance, the interplay between subsystems such as the
calibration unit (CAL) with the AO bench. We report on-going optimizations on
the AO controller loop to filter vibrations and last but not least achieved
contrast performance applying speckle nulling. Furthermore, we will give an
outlook of possible but challenging future upgrades as the implementation of a
predictive controller or exchanging the conventional 48x48 SH WFS with a
pyramid. With the ELT era arising, GPI will proof as a versatile and
path-finding testbed for AO technologies on the next generation of ground-based
telescopes.
