From now until March 21, PlayStation 3 owners can sign up to be a part of inFamous 2’s Mission Designer beta; the signup page can be found here. After the 21st, a select group of people will be chosen to take part in the official Beta testing period beginning on April 12th.
The PlayStation US Blog reassures gamers that vouchers will be released in staggered bursts, so not everyone will be selected right away to engage in the Mission Designer beta. At the moment, the beta is only open to United States residents.
According to Sony, the user generated content for inFamous 2 will be an integral part of the game, which will be released in June.