IGN that the service will not be available on PS3 this year.
The reason for the switch remains unclear, though Microsoft announced a partnership with the NFL during its Xbox One reveal event in May that has yet to be clarified. The partnership involves live broadcasts of NFL games through Xbox One. Additionally, those that pre-order the special edition of Madden NFL 25 through Amazon this year receive a free year of NFL Sunday Ticket's PC and mobile service.
PS3 owners won't be totally in the dark, however, as the console received a new Live Events Viewer app this week. The app offers both free and pay-per-view streaming options for sporting events and other live entertainment events like concerts, starting with WWE's SummerSlam this Sunday. Live Events Viewer is free to download from the PlayStation Store.
Update: DirecTV has confirmed with Joystiq that NFL Sunday Ticket will not be available on PS3, nor will it be available this year on Xbox 360 or Xbox One.
Update #2: DirecTV has also confirmed that NFL Sunday Ticket will not be available through the PS4.