Germany 2011

The husband and I have been talking for some time about taking our first trip across the ocean some time next year, and have finally decided on a destination and time frame.
Destination: Germany
Time: August 2011
I want to attend the Wacken Open Air festival, which will be taking place from 4 to 6 August 2011. The husband also wants to take a turn around the Nurnburg ring. Here is the route I have planned right now:

• Fly from Jo’burg to Hamburg to arrive 3 August 2011.
  
• Make our way from Hamburg to Wacken for the 4th, spend 2 days at Wacken
  
• Return to Hamburg for a day or so, and then make our way down to Nurnburg where we will spend at least 2 days
  
• Make our way to Frankfurt, spend a couple of days there and then fly back from Frankfurt to Jo’burg.

View Germany trip 2011 in a larger map
I’d love some suggestions of things we can do along the way, or any tips on planning our trip or anything else that may be useful