The official Japanese website for inFamous: Second Son hints at continued support for user-generated content, a la inFamous 2.
Spotted and translated by Dualshockers, the website lists "Online: Supported" among the game's notable bulletpoint features. Apparently, Japanese game websites like this one don't usually mention online support unless it involves multiplayer gameplay.
However, a similar listing for Killzone: Shadow Fall on the official Japanese PlayStation website indicates that one to 24 people are supported in online gameplay. Without any such information for inFamous: Second Son, it stands to reason that any online functionality won't extend to competitive or cooperative gameplay.
Previously, an E3 2013 brochure given to Videogamer listed "Online players: TBC" for the game. Developer Sucker Punch has yet to comment on the existence of both multiplayer and user-generated content for Second Son.
While limited in scope and complexity near release, creations in inFamous 2 and inFamous 2: Festival of Blood have blossomed to include grand storylines and highly creative constructions. Early problems included player disinterest after trying buggy creations and the lack of a keyword-search system until a week and half after inFamous 2's release.
An inFamous game for PS Vita may be distracting from potential multiplayer developments on Second Son. Last September, inFamous game director Nate Fox gave a flustered reply when asked about what future the franchise could have on Sony's portable: "Right now, we're only talking about the PS4 game... I'd love to tell you about any Vita related titles when... or, if, the time comes."