Robert Downey Jr. sure likes his surprises. The actor tweeted out news Monday afternoon that there would be a "Big #Avengers announcement" on Tuesday's episode of Good Morning America. Along with that was a picture that Downey says is a clue:
— Robert Downey Jr (@RobertDowneyJr) April 6, 2015
The picture looks to be the shoulder armor for one of the Iron Man suits Downey wears as Tony Stark in the Avengers: Age of Ultron movie, specifically the one seen in this solo poster seen at right. The white overlaid graphic is unable to be made out.
Note that last time an Avengers announcement was teased by Downey in this manner, it was a trailer for Avengers: Age of Ultron. With us now having seen over a dozen trailers, clips and video packages, this new announcement would seem to be something else.
One of the big mysteries from Avengers: Age of Ultron has been the official look at Paul Bettany as the Vision. The "reveal" on that would seem to be due now as countdown to the movie's debut goes from months to weeks. Perhaps the clue Downey has is a puzzle-piece to a container which the Vision emerges from. Perhaps its a clue that a new trailer, TV spot or featurette is coming featuring Bettany as the Vision.
Also, this might seem completely out of left field, but given the blockbuster success of Furious 7 and star Vin Diesel's teasing of a second role for him in the Marvel Cinematic Universe outside of Groot, if there were a Diesel-Marvel announcement to be made then this week might be the opportune time to make it.