A couple of months after it was announced, Sony have today made their latest version 4.0 firmware for the PXW-FS7 available for download. The biggest improvement for many users will be the rapid access to slow motion settings and support for XAVC-I at true 24 fps in 4K.
   

Here is the list of official enhancements:

1. Support for Flexible Spot in Focus setting.
2. Support for XAVC-I 4K 24.00P.
3. Display for Video Signal Monitor is improved.
4. Operability of S&Q setting by assignable button is improved.
5. Remove Basic Authentication from items saved in all file.
6. Auto knee stability is improved.
7. Overall stability and operability of the camera is improved.

You can download the new firmware here.