Empire of the Sun is the new collaboration between Australian musicians Luke Steele and Nick Littlemore. Steele is the vocalist/guitarist for the band The Sleepy Jackson and Littlemore is part of the electro duo Pnau. Walking On A Dream is the first single from their forthcoming as-yet-untitled album. Not a TON of info out there about the group, but The Inspiration Room has a good write-up.
Check out the Empire guys on their Myspace and visit the website for the single at walkingonadream.com where you can download the Sam La More remix. Not sure when the LP will drop but I'll be keeping an eye out for it.