An extrasolar planet, or exoplanet, is a planet outside the Solar System.
By far most detections are made by 'Radial Velocity' variations to the sun which is centric to that planetary-system.
http://exoplanetarchive.ipac.caltech.edu/
The latest NASA Exoplanet Archive image shows a total of 778 such planets (in 624 planetary systems, including 105 multiple planetary systems) have been identified as of August 24, 2012.Artist's impression. Hmmmm Planets .... Droool.
Current Exoplanet Archive Holdings
793 Planets around 627 Stars
2,320 Kepler Planetary Candidates
1,889,798 Transit Survey Light Curves