Disney's FastPass has been a staple at Walt Disney World and Disneyland for about a decade now. The system allows guests to effectively obtain a reserved ride time later in the day, dramatically reducing the amount of time guests must wait in line for some of the more popular attractions.
Currently the system provides equal benefits to all guests. However, there have been persistent rumors of Disney further developing the system in ways which would allow them to dole-out FastPass benefits differently to groups of guests (i.e. those staying in on-site resorts may get a different FastPass benefit than those staying off-site.)