That letter I posted from DL is from 2 days ago. I'm going to go with 70 pounds and 115 linear inches.

Additionally, you're right, Tide about 50 pounds internationally, but it is 70 for medallions domestically:

http://www.delta.com/help/faqs/bagga....jsp#medallion

Can Medallion members continue to check bags at no charge?

Medallion members traveling on U.S. domestic flights in the Economy cabin are permitted to check two bags up to 70 lbs. each free of charge. (International flights allow 2 bags up to 50 lbs.)