From July 7 to September 30, 2010, Hilton HHonors members can choose to earn double points or double miles for stays. Registration is required and if you select double miles, you must have your earning preference set to points and miles. All partner airlines will be participating in this promotion and most airlines offer 500 miles per stay as the normal number of miles credited per stay. If you choose to earn miles with bmi, you can earn 1,000 miles per night (not stay) on up to three nights. Complete a three-night stay during this promotion and you can earn 6,000 miles per stay if you choose bmi as your preferred airline. Visit http://www.hhonors.com for more information.