How about a python script using v4l2-ctl that will enable you to change focus and turn on/off the led while filming a video?

Well, m2cm2c over talk.maemo.org has maked the script works while filming video!

It does the following with the N900 keyboard :

q-w led on/off
e-r recording red light on/off
a-s change focus
z turn off the zoom and enable the focus through the zoom buttons
c turn on the zoom and disable the focus through the zoom buttons
d fixes the sudden focus that happens sometimes after pressing the camera button,so press d first then adjust the focus with a and s so you don't get a different focus than the one you got with the camera button.
x terminate script

* remember to always press X on the keyboard when you're done with the script 

Here's a demo video of the script working :

Once you've installed the deb file, you can run the script by clicking on its icon from the applications menu and then start filming !

You can this space for upcoming updates !

Download it !