The email led to a new privacy statement, which includes this phrase, among others:
We may use the personally identifiable information a user submits for any purposes related to our business, including, but not limited: To allow us to contact you by phone and/or email.
Fortunately, the email included a way to opt out (see below), so that's what I'm going to do next. You many want to do the same!
>> You can ask us to stop processing your personal data or contacting you for marketing purposes at any time.
* For SourceForge.net, please contact us at firstname.lastname@example.org
* For Slashdot, please contact us at email@example.com
* For FreeCode, please contact us at firstname.lastname@example.org
* For SlashdotMedia.com, please contact us at email@example.com