100,000 Membership Rewards points from the AMEX Platinum card - It's back!

EDIT: Offer is dead, lasted 6 hours 

My friend just let me know that the American Express Platinum card is now offering a huge sign up bonus of 100,000 Membership Rewards points after spending $3,000 in 3 months.  The normal sign up bonus is only 40,000 points so this bonus is huge.  

While this card has a hefty $450 annual fee not waived the first year, there are a few nice benefits that help to offset the annual fee.  With the Platinum card you get free lounge access, Hilton Gold status, Starwood Preferred Guest Gold status, $200 yearly airline fee credit, and extra benefits such as Global Entry or TSA Precheck credit.     

If you select United Airlines for your Airline Fee Credit, then download the United MPX app for your phone, you can purchase a $200 Amazon.com gift card and then get a $200 statement credit on your account.  The Airline Fee Credit gets renewed each calendar year.  If you keep this card for one year, then the $450 annual fee can be offset with $400 worth of Amazon.com gift cards airline fee credits.  Edit: Amazon gift cards via the United MPX app NO longer trigger the statement credit.  AMEX stopped this.

American Express has upgraded the card benefits by adding 5x points on flights booked directly with airlines or with AMEX Travel, 2x points on trips booked through AMEX, and 1 point per dollar spent on everything else.  

You can apply for the AMEX Platinum card here.  Note: the link works if you open "incognito" mode on your web browser.  This offer comes around once in a while and it doesn't usually last long!  Read more discussion about this card in the Reddit thread here.  

Note #2: Do NOT under any circumstances do any manufactured spending such as buying gift cards with your new Platinum card. American Express may and can freeze your points balance.  See this Flyertalk discussion for more details.