Shock 'till they drop.
inFAMOUS follows the open world philosophy to the letter, giving you a large area full of various props, enemies, collectibles, and missions to explore as completely or thinly as you desire. That sort of formula has been done numerous times, in fact, it has been done so many times that it is hard to justify ever playing these games without it having something significantly different or improved. So, I suppose the real question is, does inFAMOUS do anything special? For me, the tight controls and interesting plot gave the game enough pop to make it really stand above other games of this type.
One thing that I really appreciate in inFAMOUS is how well it plays in general. You feel very in control of the electricity filled protagonist, Cole, and while some of his powers are bursting with seemingly uncontrollable energy, I never really felt like I was struggling to accomplish what I wanted to happen. The game also runs well from a technical standpoint: the visuals are well done, and I never experienced any of the significant slowdowns, texture pop-ins, or slow loading times that many other current games suffer from. Really, inFAMOUS accomplishes something that most other open world games fail at right there - by making a game that plays the way it should.
The combat in inFAMOUS is pretty strong, but certainly isn't perfect either. Since the game features the industry standards regenerating health and cover mechanics, many fights boil down to the basic third person shooter feel. However, when you get into the mix of things, and start throwing off all the powers allotted to you in the heat of visceral combat, everything gets alot more fun. It's just a shame that the game doesn't encourage you to play this way, because it is actually much harder to do so. Still, the lightning based abilities you acquire are all cool and unique, and there seems to be the perfect number of them so you don't feel overwhelmed while still being extremely versatile. The traversal mechanics are also generally implemented well, and you can fly across the city rooftops as fast as you could hope to, and suffer basiccaly no messups due to sloppy controls. In fact, rather than messing up and falling all the time, you'll most likely get more annoyed with Cole "sticking" to spots you didn't really want to end up in.
For me, the best thing about inFAMOUS was the last thing I expected to love, and that's the story behind it. So many open world games just let the story be a very bland backdrop to your adventure, but inFAMOUS actually spends the whole game crafting a plot that, is some ways, doesn't begin until the game is over with, but really in the end makes you feel like you know exactly what this game was about, and how all the major figures play into it. I won't say much on this for obvious spoiler reasons, but suffice it to say that even with the somewhat slow beginning, inFAMOUS really takes care into crafting an interesting new world. Probably the last main thing to talk about is another mechanic that seems to be fast on track to becoming an industry standard: the karma system. inFAMOUS is, unfortunately, the king of contrived karma systems, and doesn't even try to hide the "gameness" of it. At multiple points in the story, the action will pause, and Cole will deliberate in his head two options: one that couldn't be more good and one that couldn't be more evil. Also, some side quests are clearly marked "Good Side Mission" or "Evil Side Mission", and completing one locks the other one to you. This may not be a bad thing to everyone, but I'm honestly just tired of feeling pigeonholed into picking good or evil at the start of every game I play.
Essentially, inFAMOUS does everything that you'd expect in an open world action adventure title, with some aspects, namely the way it controls and tells a story, exceeding those expectations. That's pretty much enough for me to recommend it to people who enjoy open world games or action adventure titles in general.