There is an agreement in placeThere is an agreement in place between Stack Exchange and Lifehacker to regurge some material for the latter's blog:
Yes. Stack Exchange does have a new partnership in place with Lifehacker. Keep an eye out for a "Crowdhacker" post published at their site once or twice a week.
At the footer of all Stack Exchange sites you'll also note that your posts are licensed through to SE via a creative commons and other sites that want to repost or slathe, should follow the rules of attribution outlined when doing so. Lifehacker has done such.