From the current Windows Secrets newsletter, by Brian Livingston, (scroll down a bit), emphasis added.
Windows Genuine Advantage ÃƒÂ¢Ã¢”šÂ¬Ã¢â‚¬Â the controversial program Microsoft auto-installed as a “critical security update” on many PCs starting on Apr. 25 ÃƒÂ¢Ã¢”šÂ¬Ã¢â‚¬Â not only causes problems for many users but has now been proven to send personally identifiable information back to Redmond every 24 hours.
This behavior clearly fits any plausible definition of “spyware.”
What we’ve found about WGA fits neatly into four behaviors that are typical of all spyware:
1. Lack of disclosure before installation.
2. Transmits data to a central computer.
3. Downloads other software and morphs itself.
4. Cannot easily be uninstalled.
Gates leaves, the delivery date for Vista (the next generation of Windows) is delayed yet again, now this, which at the very least will be a PR nightmare for Microsoft among the highly influential tech community. And deservedly so.
WGA is forced upon your computer. If you want Windows Updates you have no real alternative but to install it.