@Munkeh111
There is no giving the demo a "quick" try, lol. The demo will last you anywhere between 30min to an hour depending on how much exploration you wanna do. Infamous by far has the best demo I have ever played.......EVER!
First mission is(DEMO SPOILERS) to stop a hostage train. You can't just blow up the tracks or anything, you have to get it to a safe destination before you can release them due to the high quantity of Reapers patroling the streets. Periodically as you are surfing on the train, the Reapers will disengage the track segments, stoping the train. You have to find the switches(underneath the tracks) and give them a jolt. Unfortunately, the Reapers are usually close by and do not let you pass freely.
When that is done you see a cutscene and move on till night time. Now you get to choose your path. You have 2-3 missions you can select at the moment. I believe the game gives you about 10minutes of leisure so you can go play, then it demands that you pick a mission. The missions also alter whether you are Good or Evil(for demo demonstration purposes). These give a good Idea of the benefits of being evil or good. You also get to meet Cole's Ex-Girl, Trish in one of these missions. Needless to say,she is not your biggest fan, but she tolerates you(more like uses you).
And even when your done with that, there is still more to do. Through the demo the Reapers will frequently take out innocents while gunning for you. You have the chance to show how awesome you are, as you can revive the fallen. When they get up the praise you to death. Do it enough times and mobs of fans start to gather around you. They take pictures and cheer you on. If you get into any battles after that, the citizens will peg enemies with rocks and so on.
GOD.......now I wanna play the demo again for like the 12th time >_>