Starwood Hotels has just announced their second quarter promotion: Double Take

Double Starpoints on stays: Earn double Starpoints® on all eligible stays from May 1 through July 31, 2013, at more than 1,000 participating Starwood hotels and resorts worldwide.

Bonus Starpoints for using the SPG App: Plus, get 500 additional bonus Starpoints for each eligible booking made through our spg.com mobile site, the SPG® App for iPhone, or the SPG App for Android™ .

Registration is open on the Starwood website: https://www.spgpromos.com/doubletake/

The vast majority of Starwood hotels are participating, but like many hotel promotions, there are a number of hotels not participating. That list can be found here.