Voice comes for free if you add Bluetooth and ProNav. I am not sure what combinations of the three options are available outside of this. Perhaps having a play with the car configurator on the BMW website might shed some light on it. I would assume that you could have any combination of the three, but voice without a 'phone or nav might be a bit short of useful functions. Equally you could go for just the bluetooth.
Gone: Fiesta - Focus - E46 320dSE - E91 330dMSport - E82 135iMSport - R55 JCW Clubman
Now: M135i with lots of toys