There are 3 types of annual passport - Fancilien, Fantasy and Dream.
Each offers different restrictions to days when you can enter the park and a variety of perks. The Dream offer no restriction on days and the maximum benefits.
Currently the prices are 89, 129 and 179 respectively.
The idea of the sponsorship programme is that if you sign up others to also take on an annual passport they get 10% off the cost of the annual passport while the sponsorer gets additional free months on to their current annual passport.
As the official site only has annual passport details in French this is often missed by many guests. As well as DLP would much prefer to sell packages
If you intend spending more than 3 days in DLRP in a year, the general opinion is its more advantageous to buy an AP.
I have a dream AP (got DD's completely free as she is 6) and I reckon, in the space of only 2 short trips to DLRP, its paid for itself . I intend going back again at least once more before my AP expires in October next year, and maybe I'll even manage to sponsor enough other AP's to extend mine for another year for free.