As always, you earn base and bonus miles. In addition to this miles, you earn 25,000 bonus miles for flying the segment ATL-LGW until June 15th and if you purchase at least a Q-fare. Bonus miles apply on transatlantic portion of travel only (no bonus given for travel beyond ATL and LGW). Remember: You must register before you begin travelling!

Relevant Links:
SM Offers: http://www.delta.com/skymiles/sm_offers/index.jsp
ATL-LGW Bonus registration: http://www.delta-offers.com/offers/servlet/Registration?offer=52037&lang=Us','Register',400,3 00