Luggage for elite
 

I have seen posted that elite travelers can check 3 suitcases up to 70 lbs each. I have been to the Delta website, but cannot find anything that says this is true at the Medallion benefits and Luggage requirements webpages. Can someone point me to where these benefits are stated?

I don't know that it is a standard benefit on all airlines. Star Alliance Gold allows an additional 20kg or one additional piece, depending on the system used locally. http://www.united.com/page/article/0,6722,1165,00.html

I could not find a mention of such a benefit in the AA Plat or ExPlat guides.

If you are interested in Delta's policies, you be better off posting in the Delta SkyMiles board. There are plenty of people there who are intimately familiar with the policies of that specific airlines.

If you are on a Song flight, you can check in up to 3 pieces of luggage up to 50lbs each for free.