The latest results from the WMAP satellite confirm the success of the Lambda CDM model, where approximately 75 % of the mass-energy density is in the form of Dark Energy, and matter, most of it in the form of Cold Dark Matter (CDM) making up the remaining 25 %. Neutrinos with masses on the eV scale or below will be a hot component of the dark matter and will free-stream out of overdensities and thus wipe out small-scale structures. This fact makes it possible to use observations of the clustering of matter in the universe to put upper bounds on the neutrino masses. Present cosmological neutrino mass limits make use of the suppression effect of the neutrino free-streaming at a fixed, given redshift. As our ability to map out the mass distribution at different epochs of the cosmic history improves, by doing, e.g., weak lensing tomography, we will gain sensitivity by in addition using the effect of massive neutrinos on the growth rate of density fluctuations. One key issue which then arises is possible degeneracies between neutrino masses and cosmological parameters. We study the degeneracies between neutrino mass and Dark Energy as they manifest themselves in cosmological observations.