I'm a little nervous but excited as well. It will be the biggest water I have done so far. I think it is rated at class 3 but there might be a class 4 in there as well. Class 5 is experts only and class 6 is considered runable.
There is a place just south of Duluth you can do white water rafting that might be more your speed. Its actually really fun, the guides are all in kayaks along side you so you are in charge of steering your own raft. That rapids are nothing like that picture though, much much smaller but you still get the heart pumping a little.