We investigate the symmetric degrees of freedom (DoF) of multiple-input multiple-output (MIMO) cellular networks with G cells and K users per cell, having N antennas at each base station (BS) and M antennas at each user. In particular, we investigate achievability techniques based on either decomposition with asymptotic interference alignment or linear beamforming schemes, and show that there are distinct regimes of (G,K,M,N) where one outperforms the other. We establish specific antenna configurations under which the DoF achieved using decomposition based schemes is optimal by deriving a set of outer bounds on the symmetric DoF. We then proceed to to develop two contrasting approaches to linear beamforming and show that they can achieve the optimal DoF of a wide class of networks.