What more can you ask for?
From the physics that enable you to climb pretty much anything, to the wide range of upgradable powers are just a few of the flawless aspects to the game.
The strong points:
Sound - It really is brilliant.
Physics - Sucker Punch really nailed the physics. Players can climb pretty much anything without making the game too easy to get around enemies. The issue of climbing over buildings to avoid a mob was countered well with the majority of enemies positioned on rooftops. Sucker Punches wisdom shone in many other aspects of the game also, but this was the main focus of thought.
Powers - Done much like 'Spider-man, Web of Shadows (which I loved), upgradable powers are the main reason to progress through the game. Unlocking new ones as you go, along with upgrades bought with exp from completing certain tasks, it'll take you the length of the game almost to get them all.
Map - The free to roam map is huge! You There's 3 islands altogether. You start on the biggest one, but the 2 after are much more interesting and you'll unlock these other 2 islands at certain points of the story. Even after you finish the main story mode, there are still many side-quests, which I chose to do along the way, and unlimited dog-fights with opponenets.
Weakness:
The only thing I have an issue with in this game is the graphics, which really aren't all that bad. The main focus for Sucker Punch was obviously the physics, which more than likely held them back from really shining with the graphics. However, the slightly animated feel adds to the comic-book style of super hero so I really can't complain (too) much about them.
Another very small issue is with sticking to every object when falling. Because you can climb almost anything, you grip almost anything when you want to go down which can be a little frustrating at times.
In conclusion, InFAMOUS is by far THE best super hero game I have ever played on any console. The sandbox can't quite compete with games such as GTA, but that's not what it was made for. The physics, huge map and fantastic story line, along with the rememberable character Cole make this game truely brilliant and one definitely not to miss.
If you're stuck between this and Prototype, for a start, Prototype is gonna be an 18, so if that's all that's holding you back, buy this now. I myself will also be getting Prototype. Personally I don't see how people are comparing these two games when 1 hasn't been released yet. Anyway, don't miss out on InFAMOUS. You WILL regret it.