When Joss Whedon revealed that Ultron would be in the Avengers sequel, but Henry Pym would not, we had a Vision of a certain scenario. There was nothing artificial about our intelligence about what the future may hold, and we went through a phase of uncertainty.
Okay, enough being clever - Paul Bettany, who has previously been part of the Marvel Cinematic Universe as the voice of J.A.R.V.I.S., Tony Stark's AI that helps drive his armor and in fact his entire life, will step out of the ethereal into the role of The Vision, the synthezoid Avenger who was originally created by Ultron to help him destroy all human life in Avengers: Age of Ultron.
With the specific casting, this all but assures that the creation of Ultron, and thus The Vision, will be connected directly to Tony Stark, who has been seen in the MCU as not only the forefront in AI technology, but also the backbone of the series of films so far.
The news broke late Friday on the various Hollywood trades, after Bettany visited with Jeremy Renner and Joss Whedon to discuss the sequel. An Android who is gifted with a soul of sorts, The Vision in Marvel Comics became a full-fledged member of the Avengers, helping take down his "father" on multiple occasions. There was even a romantic relationship with Scarlet Witch - also making her debut in the film played by Elizabeth Olsen - which led to twin boys (with a little help from some chaos magic).