I fly about 50,000 miles per year. 4 of those trips are overseas in business class. Does the attractiveness of Delta depend on full fare versus, for example, internet fare? That is the way AA does it. NW counts most miles as the same.

Does DELTA no longer automatically upgrade Medallion members to business/first on domestic flights? I am currently with NW and that is what they do.

What am I missing (Compared to NW).