Raspberry Pi firmware compatibility

[Pihkal]

Hi,

i'm wondering when Xbian will be compatible with the latest RPI firmware?
I've tried to update the firmware (at my own risk ) but the rpi-update command isn't recognised.
I know it's advised not to update but if it breaks i'll just revert back,no biggie.
In case you're wondering why i want to update the firmware:

my mpeg2 license doesn't work so i've started a thread on the r-pi forum,Dom (the guy who writes the firmware) suggested my firmware was outdated and i should update it.
But i can't...
Not that i think it would resolve my issue.

Greetz