From Astral Doors website:
"In agreement with the promoter of ProgPower USA (Glenn Harveston) as well as our management (Intromental), we have decided to turn down the offer of playing at PPUSA in Atlanta, Georgia this year. The reason is simply that we have to do some more European touring in 2008 before going to USA, and thus our economy won't allow us to make this trip yet. Instead we've made the great deal with PPUSA that we'll perform, come hell or high water, at the festival in 2009. Thanks to the promoter for helping us make this hard decision much easier for all concerned. "