A Reddit user has been uploading promo art from Avengers: Age of Ultron - posters, t-shirt images and toy packaging. Most of this stuff isn't interesting, but the back of Vision and Ultron figures seem to give away the origns of the two robots (or the robot and the synthezoid, rather), and they're different from what we expected.
They're certainly different from what I expected, having access to an early draft of the script. Here are the bios. Be warned if you're afraid of minor spoilers:
Two things stand out to me: Ultron's origin as Chitauri programming gone wrong and Vision's origin as a good guy. In the script I know there was a great - probably iconic - scene where Vision is revealed, and this bio makes it sound like that scene could be undercut. Or is it just stuff to fill a toy bio? It could be information revealed here in a straightforward way that is revealed in a more interesting way in the movie.
In the comics Ultron creates The Vision (using the brainwaves of a dead character, Wonder Man*, which is why everybody thought Phil Coulson would become The Vision), and I always liked that origin for the character. That said, the Science Bros teaming up to make him is nice as well. Everybody loves the Science Bros. As for the Chitauri programming - I don't have that in my notes from the pre-shooting script, so I don't know if I just missed that or if it's a new addition to Ultron's origin.
There's a whole ton of other art that leaked, including this cool image of Thor standing amidst a pile of dead Ultron drones:
And this image of Ultron holding the whole world in his hands:
These are not images from the film - they're promo and branding art. You might see this stuff on t-shirts or toy packaging or beach towels or video games (actually the borders make them look like they could be on collectible trading cards, if you ask me). They're just kind of awesome is all.
* and also parts of the orginal android Human Torch. Or maybe not. The whole thing got complicated and retconned. I'm not actually sure where the relationship between the Torch and Vision stands today.