Are you viewing the lauch from the visitors complex or taking the bus out to the causeway? Either way it is a great experience.
We went last year and had a great time. The Dine with an Astronaut is a great thing (I wish we had done that, the lines for food elsewhere were NUTS).
There is a thread on the Hotels board that has some great info on launch viewing.
Here are a couple of pictures from our launch STS-115.
They had a couple of Jumbotron screens set up and piped in the audio so you could keep upto date with what was going on.
There is also a Launch Status area, where they were giving updates and talking about the preperations the Astronauts and the Shuttle go through prior to launch.
If your going out to the Causeway they have the same audio available via loudspeaker and they also have food & merchandise for sale. There were tents set-up with chairs if you wanted to stay out of the sun, but a lot of people brought thier own chairs and waited it out.
Shuttle on the Launch Pad, it will be closer this time as they are using the other launch pad.
Lift-off