The powers you start with are good fun, but you earn experience points as you complete missions and defeat enemies
There's plenty to keep you interested in the game. Like SM2, you work your way around the city, starting parts of the main mission when you want to, or completing hugely entertaining side missions. As you explore, there are various collectibles to keep your eye out for, which add to plot, or increase the reserves of electric energy you can channel.
The powers you start with are good fun, but you earn experience points as you complete missions and defeat enemies, with which you can buy new powers. And it has to be said, the enemies are a lot harder to defeat than I thought they would be. You start the game with some fairly basic electric powers and you are by no means invincible - you frequently have to duck behind cover to allow your health to recharge and unless you position yourself carefully, you can easily be overpowered by a group of 3 or 4 Reapers (the bad guys in the game).
The Reapers make for good enemies too. Even the entry level ones have got pretty advanced AI - they duck behind cover, throw grenades when you do likewise and scatter when you throw grenades at them. As you advance through the game, they become harder to kill and have much more powerful means of attacking you.
But my favourite part of the game is the main character's means of getting around the city, which consists of scrabbling up, around, over and between buildings, in an advanced version of parkour. I could happily spend ages just monkeying my way around the city, if it weren't for the wealth of things to do aside from that.
This'll keep me busy for ages - or at least until Prototype comes out in a couple of weeks.