I'm not sure if the credit crunch will effect the Hosting Industry in a big way,well,but Its obvious to say that If It will effect the Industry,It wont be in a positive way.
However I think the Hosting Industry is sort of recession proof,not 100% but some what,however this will effect small and medium Agencies,especially Companies that are looking to come into business as there is need for Finance in buying the hardware.
But I still think there wouldn't be a large Shift in customer base.