I finally got the 50k offer today after weeks of trying. Finally made my account here to share the details. I had tried 3 computers, 7 total browsers, over 50 attempts and none worked. I got it today by heading to www.americanexpress.com
(on Firefox not incognito for the record), clicking "CARDS" at the top, Choosing "View All Personal Charge & Credit Cards" from the dropdown, Choosing "Check for Pre-Selected Offers" from the next screen, and filling out the information. Was offered this deal as well as 25k for Everyday and Everyday preferred.
Obviously this probably won't work for everyone, but all the other attempts at card matches recommended to get this offer never worked for me. This did.
Got approved with ~750-770 credit and 37k income. Had applied for Discover It two weeks ago (approved) and Chase SW Premier on Christmas Eve (decision still pending). Probably going to need to look into manufactured spending or buying things for parents/friends if I get approved for the SW card. $1000/month ($2000+$1000 in 90 days) on things I can use a credit card for seems overly luxurious since finding MMM.
Assuming I get the card in by 12/31, anyone know if I will be able to use MPX app to get the Amazon gift card and have the $100 reimbursement count towards 2015? Otherwise I will need to set a reminder to do it again in a year if I end up canceling the card.