The knobs are no longer a "separate" piece; MINI has gone to a one-piece knob/boot/trim ring assembly.
That said, the knob CAN be removed from the boot; it simply snaps into place,
and can be pulled off.
The boot material folds over this small plastic small ring, and the stem underneath the shift knob snaps into the ring.
In addition to going to the knob/boot/ring assembly, they have also lengthened the distance from the top of the lever to the locking groove, which means a pre-07 knob will not fit an 07 car properly, and vice-versa.
If you have any questions about the Whalen Shift Knob and the 2007 MINI please email me.