If you like the idea of the spectacle of Killzone 3 but can't justify plopping down $60 for the game, there will soon be a solution for you. A free download will be showing up on the PlayStation Network next week that will allow players to jump into the online multiplayer version of the game. Of course, all the limits that typically come with a free-to-play MMO will be in place.
That is, there will be a level cap (specifically, the level of "Sergeant" will be the highest rank possible). However, for a one-time charge of $14.99, players can max out their character with no limit. That's still a pretty small price to pay considering it opens up access to not only the base game map but all the additional maps that have been released through DLC packs as well.
The freemium model has become the de facto way to monetize online games these days. In fact, in the world of apps, the freemium model has exploded among games that are mainly played offline as well. Because of the ubiquitous nature of broadband connectivity, the hard part is no longer getting a game into someone's hands. That's easy. So by pulling players into the experience and getting them hooked, the lifetime value of a game is increased significantly.