This is an absolutely beautiful game - and a strong performer. Across a general run of play, inFamous: Second Son spends most of its time north of 30fps.
There's been some discussion about the performance of the game, particularly in terms of a fluctuating frame-rate, and what quickly becomes evident is that Sucker Punch has opted to continue the strategy it used on its PlayStation 3 titles: a solid v-sync working in combination with a completely unlocked frame-rate. The difference here is that while the previous titles in the series would frequently drop beneath the 30fps threshold, it takes a mass of action and GPU-intensive post-processing effects to truly impact inFamous: Second Son's performance. Bearing in mind the high levels of detail, and the overall complexity of the rendering pipeline, that's a stunning achievement.
However, the disadvantages of the unlocked frame-rate are pretty clear when looking at the frame-time graph. Here, we study the amount of time each individual frame is on-screen. A locked 30fps or 60fps gives a level of consistency that is considerably easier on the eye, and helps to ensure a level response in terms of controller input lag. inFamous: Second Son spends much of its time between 30-40fps during gameplay - those additional frames over 30fps manifesting more as judder as opposed to a significantly smoother experience. It's hardly a massive issue, but a Killzone-style frame-rate limiting option would be welcome.
Also worthy of note is the implementation of state-of-the-art anti-aliasing, believed to be a variant of SMAA T2X, as found in Crysis 3. This is one of the best post-process anti-aliasing techniques we've seen, combining a new take on MLAA with a temporal element. Edge-smoothing is phenomenal, and while there is some ghosting, it is not any kind of real distraction during gameplay.
We've only just scratched the surface of inFamous: Second Son right now. Indeed, the video above constitutes the entire amount of time we've spent with the game thus far - but what's clear is that as a technological statement, this is exceptionally strong stuff, especially bearing in mind that this is a first-gen PlayStation 4 title.