Brake fluid change frequency

[linq]

I just booked my B9.5 in at my local Audi dealer for an oil change/inspection service - the car's two years old and has done 10,000 miles. The following day I received an email from them entitled 'It’s time to change your brake fluid'. I was curious to know what others thought was a sensible frequency for replacing brake fluid? My wife's Mini has a service plan and that recommends changing it every three years. Is a first change at two years necessary?

[Elpeterol]

I had mine done at first service/ 2 years seems standard for Audi. Probably worth it on a performance car as the boiling point can go down with age.

[Jools]

The modern brake fluids absorb water over time, the old stuff lasted for ever but apparently wasn't very kind to the environment as a result it needs changing reguarly.
It also means Audi have another reason to empty your bank account!

[linq]

Thanks for the replies. I must admit I didn't know the formulation of brake fluid had changed. I'll get it replaced.
Ian