Guess Maxis made true to their promise, as they finally got around to adressing a de-authorization tool for the game.  This was sent to me via MaxisCactus:

Hey Everyone,

In recognition of player feedback regarding DRM and SecuROM on Spore, Maxis is offering a standalone download so that users can now “de-authorize” a computer if they would like to make that authorization available for another machine.

Machines can be de-authorized or re-authorized at any time. The total number of machines on which Spore can be authorized concurrently will continue to be five. To de-authorize a PC, download and launch and run the Spore De-Authentication Tool.exe file.

You can de-authorize at any time, even without uninstalling Spore, and free up that machine authorization. If you re-launch Spore on the same machine, the game will attempt to re-authorize. If you have not reached the machine limitation, the game will authorize and the machine will be re-authorized using up one of the five available machines.

Thanks everyone for your feedback, we hope you find this tool useful.