I have been gradually working my way to 2MM with both flying and my regular Citi AA card. I don't think I will continue since my current card is free and the Citi new deal is $450 a year.
I think I will change to the AMEX Platinum which gets me into both the Admirals Club and Sky Club on DL plus a lot more bennies for the same $450. One year flying plus spending on the new Citi card will not get me close enough to the 2MM to be worth the limited bennies compared to the AMEX Platinum.
Glad I get to keep my lifetime Gold for my current ~1.6MM
Cheers