Thor: The Dark World - VFX Making Of
Go behind the scenes on the VFX created for Thor: The Dark World.
Battle for the Avengers Tower 360°
The Avengers battle Ultron's minions in this 360 degree video (available on Android phones or Google Chrome).
Avengers: Age of Ultron - Casting the VFX Vendors
fxguide have created a very thorough article about the VFX vendors contributing to the massive Avengers: Age of Ultron.