Apparently Jam Packs can no longer be installed on Lion. I just recently attempted to install the 'World Music' Jam Pack that has been lying around my house, but once i got down to the one minute remaining mark, I was relentlessly bombarded with alerts that read something along the lines of "Cannot open the application PListBuddy because Power PC applications are no longer supported." This is obviously a significant problem, and it needs to be fixed. You would think Apple would have foreseen and addressed the issues that this migration from Power PC applications would yield, but evidently they have not.