Delta SkyMiles members can earn up to 1,000 miles for downloading the SkyMiles Shopping Assistant and spending $250 or more through Dec. 31, 2011.
Download the SkyMiles Shopping Assistant and you'll earn 500 miles when you keep it installed for at least 30 days. Spend a total of $250 (not including taxes and shipping fees) at participating retailers with the SkyMiles Shopping Assistant and you'll earn another 500 miles.
The Shopping Assistant is only compatible with Windows XP, Windows 7, Windows Vista platforms and Internet Explorer 7,8 & 9, Firefox 5,6 & 7, Chrome 11,12 & 13. The tool is not yet compatible with Macs.
Source:
