In commemoration of the PlayStation Network getting back up on its feet, Killzone community editor Victor Zuylen announced that Killzone 3 players will be treated to some double XP goodness this weekend.
The double XP weekend will run until Monday, May 23 at 1000 hours GMT. In addition, it isn't the only Killzone package wrapped up in ribbons for players. Killzone Liberation is part of Sony's "Welcome Back" programme and is being offered free of charge.
Zuylen also added that "there's even more"¦But [they'll] announce that at a later date."
Source: PlayStation Blog