SoundPackager packages are meant to be edited by all, and easily. Additionally Windows' sounds are defined with the system on a per-user basis (Microsoft's choice, not ours). Because of this, they fall moreso under a per-user file. The good news is that we will be allowing users to choose the directory which SoundPackager looks for the SoundPackages, in the next beta.
A question, if I may, Andrew:
With Soundpackages being currently kept in my (pictoratus') Documents folder, wouldn't this keep other users from accessing those files?
With the current setup, it seems as if each user on a PC would need to download their own copy of say the Baseball package rather than a single downloaded package accessible to all users.
I'm thinking the Stardock folder under Shared Documents would solve this potential issue; which I think is where Neil was going with his explanation.
Perhaps individual user's sound profiles would go into their My Documents/Local Settings to keep everyone's settings separate, with a common area for the actual sound files/packages.
Then again, I could be wrong.
Kudos on the Directory choice coming in the next beta. More choice is usually better.