Based on the images we are looking at, it looks like there have been several aesthetic changes, namely its on-screen QWERTY keyboard that seems to be reminiscent of Windows Phone, a swipe-to-unlock feature, updated UI for the browser, music player and options screen. According to whoever sent these screenshots in, the Carla update is expected to be available for the Nokia 700, 701, 603 and the 808 PureView, while first-gen Symbian^3 devices like the Nokia N8, E7, C7 and C6-01 will not be eligible.
So what do you guys think? Could this really be the Carla update that we are looking at here? Until an official announcement has been made, we will be taking this with a grain of salt for now.