About a week ago I also was in the Gelredome. Then it was for a Prince concert, this time it was work; Qlimax 2010.
Definetely not my kind of music, but work can't always be perfect. And since none of 'my engineers' could go, I had to go myself.
Some artists announce their concerts months in advance, but not if you're Prince Roger Nelson. Then you announce it 2 weeks before you're coming.