Now that the Delta and Northwest Merger is official, there are lots of questions going around.  The following information is directly from the Delta website.  

"Where can I get the latest merger information?

Visit delta.com and/or nwa.com for the latest merger news. If you're a frequent flyer member, update your SkyMiles profile information or WorldPerks contact information to ensure you receive the latest updates. You may also register to receive emails from either airline during the transition. Set your SkyMiles email preferences or visit nwa.com for more Northwest information.

For specific Delta inquiries, contact Delta via email or call Reservations at 1-800-221-1212. For specific Northwest inquiries, contact Northwest Airlines via email or call Reservations at 1-800-225-2525. "

For more information, go to:    http://www.delta.com/help/faqs/merger/index.jsp?MkCpgn=EM081029TNUPOTDLNWANWA-A-A-J#latest