I visited the Oktoberfest a few times. It is a big event, with thousands different people coming from all over the world. There are some very big pavilions with so many liters of beer. The peoples only ride the attractions and drink beer, all the time.
I think it is nice, if you never have seen this before, because you´ll finde there some of the biggest transportable coasters and attractions. However, don´t forget the beer, you´ll only get it in a big 1 liter glass.
Warning: don´t drink to much beer, because I saw there some very awful drunken people.