Through the official Playstation Blog come some new details about how the Infamous 2 beta is going to work. To get a chance to get in you'll need to be a Playstation Plus-subscriber and even then you're not guaranteed a spot since they will be limited.
The beta will focus on the mission architect-part of the game, and Sucker Punch will choose the best missions created during the beta and include them in the full game that will arrive in late May. More details about how the whole thing will look can be expected when we close in on the beta-date.