  Quasi-periodic oscillations have been seen in the light curves following
several magnetar giant flares. These oscillations are of great interest as they
probably provide our first ever view of the normal modes of oscillation of
neutron stars. The state-of-the-art lies in the study of the oscillations of
elastic-magnetic stellar models, mainly with a view to relating the observed
frequencies to the structure and composition of the star itself. We advance
this programme by considering several new physical mechanisms that are likely
to be important for magnetar oscillations. These relate to the
superfluid/superconducting nature of the stellar interior, and the damping of
the modes, both through internal dissipation mechanisms and the launching of
waves into the magnetosphere. We make simple order-of-magnitude estimates to
show that both the frequencies and the damping time of magnetar oscillations
can evolve in time, identifying three distinct `pathways' that can be followed,
depending upon the initial magnitude of the mode excitation. These results are
interesting as they show that the information buried in magnetar QPOs may be
even richer than previously thought, and motivate more careful examination of
magnetar light curves, to search for signatures of the different types of
evolution that we have identified.
