Here is a video by (mirrorlessreviews) showing the AF speed improvement of the recently released firmware for the NEX-5N. I think it has the same AF speed now as the NEX-7. Kudos to Sony for continuing to improve on the NEX cameras. I just hope they will also release some firmware for the NEX-C3, NEX-3, NEX-5 cameras.
Hoping that a firmware is also in the works for the NEX-7.