The frequent flyer programs at Northwest and Delta are now officially linked. Passengers can officially connect their accounts to transfer miles between the two and even earn some free miles in the process.
Delta SkyMiles and Northwest WorldPerks members can transfer miles between both accounts at no charge and on an unlimited basis, according to the Delta release
One of the best perks? You'll earn 500 bonus miles for doing it.
Members who link their accounts before March 15, 2009 will earn 500 bonus miles.
Both accounts will function "until late 2009" when the plans and airlines finally merge in 2010. To link your accounts, visit this Delta site
for more information.