Hilton just announced their next promotion where between March 1 and May 31, 2015 you can earn double points or double miles on all stays.
While I still miss the free night promotions from awhile back, double points works well for almost everyone as it is simple and doesn’t require you to swap hotels every night to maximize. It is a straight forward promotion and you get to decide if you want the double points or miles. Typically, for the average person, I’d recommend selecting points. For those that prefer to earn miles, you need to ensure that you select “Points + Miles” as your earning preference (related blog post on double dipping with points + miles).
As with any promotion, you will only get the double points for eligible stays. This means that it must be a paid reservations booked directly with Hilton, not those using a third party booking reservation system (i.e., Hotels.com, Travelocity, etc.).
Like all other Hilton promotions, some hotels have decided to opt out of the promotion and you will NOT receive the double points at those hotels on the list. The entire list of hotels that have opted out is right here. As always, there are many hotels that are not participating. I highly suggest taking a look so you are not disappointed later on. It is absolutely ridiculous how many hotels are ineligible. Also, you MUST register for this promotion prior to checking out of your first stay. Hilton will not retroactively give you points for prior stays within the promotional time frame.