I'm a little confused (got one too). Did Google sell my contact info to Gilt?
they simply gave you the option to register with Gilt if you are interested in purchasing the chromebook.
The email I got says right there: Remember, you must use this email (...) to access the sale
If so, that is why you got the e-mail.
A few months back, you asked to be notified about the availability of Chrome OS, which is why we sent you this one-time notice. You will not be emailed again regarding the availability of Chrome OS. Remember, you must use this email -- xxx.yyy.com -- to access the sale
So how did my contact info get from Google to Gilt? Did I explicitly give permission for that when I signed up? Does Gilt and/or Google profit from this?
It is possible that you gave Google permission when you signed up.
I think it is more likely that the URL has all of the information Gilt needs to process the request:
http://www.gilt.com/google-
chromebook?opromo=Google_Chromebook&ocl=Email&ocat=Link&
email_address=<any email would work here>