If you think about it, though, changing a campaign aspect is a pretty profound thing. It's just a few words. A short phrase maybe. But going from:
When The Stars Are Right
CASE NIGHTMARE GREEN
is freaking huge. The world is pretty much over, and just because some words changed.
So the next time I hit a campaign milestone, given of course that it's appropriate, I'm going to try to practice changing the campaign aspect in the smallest way that gives the most impact. It's really easy to succumb to the urge to keep adding aspects to the campaign - I think it's a lot harder to just change one and have it reflect all of the changes you want in the setting.