New MacBook Air

What are the chances of Apple releasing a new Macbook Air at WWDC?

With Haswell on board, do you expect an improvement of the battery life? Will we be getting 10 hour battery life or will Apple use this opportunity of putting in a smaller battery pack to make the device thinner?

I am also looking at 13 inch Macbook Pro with retina display. I don't think they will be putting a retina screen on the MacBook Air. The 2012 version got a bad review because it was underpowered. Will there be an improvement on performance this year?