Here is the latest information.
The Forfait Loisirs for Versailles and other sights has been discontinued.
Le Passeport for Versailles still exists, but Rick is wrong. It doesn't include transportation. It is an admission pass only which includes the audio guide and the fountain shows (weekends and holidays).
Under normal circumstances a Paris Museum Pass should allow you to skip the lines at Versailles. Here is a quote from the pass site:
"Entrance with the pass via the temporary Vinci pavilion. The PARIS MUSEUM PASS gives access to all the sightseeing excursions open according to the season: the 17th century Chapel and Hall, the State Apartments of the King and Queen, the Apartments of Mesdames daughters of Louis XV, Apartments of the Prince Heir Apparent and Galleries of the 19th century History of France and the domain of Marie-Antoinette. Not included: shows, musical water shows, audio guides, conferences, restaurants and transport services. Please note: in 2003, the Versailles estate inaugurated a vast restoration operation aimed at modernising infrastructure and public facilities. The first stage of this operation will be completed in 2009. Until then, priority access with the PARIS MUSEUM PASS could be interrupted during short periods for security reasons. Thank you for your understanding."
For a complete list of your transportation ticket and pass choices for Paris with links to detailed explanations of each one, go here.