I did this a few weeks ago and i just got the miles in my account. Really an incredible deal, 6/10ths of a cent per mile. This offer appears to be open to residents of all countries. If you are signing up more than one person in your household, I would consider using a business address and a home address and possibly 2 separate credit cards.
If you think you don’t fly on Delta that much, you should also consider that these miles can also be redeemed for free flights on Continental or Northwest.
The terms and conditions of the offer say that you need to be a Priority Club member (so sign up before taking advantage of the offer) and that you have to have selected Delta Air Lines as your preferred earning partner (so set this up also before taking advantage of the offer). You also have to be a Delta Skymiles member first as well, Delta.com.
Click Here to Register for 25,000 Miles
This deal is courtesy of the great folks at Flyertalk.com