Well, Rockstar kept their promise, and released new screenshots:

The first screenshot shows us the second return of the parachutes, last seen in the previous title "The Ballad of Gay Tony". The character is seen to be near a mountain.

The second screenshot shows us a tennis field, which showes us a new activity for the game.

The final screenshot shows us a race of dirt bikes, the Sanchez bikes will reappear in the upcoming title.