A new publication in PLoS Computational Biology from Boris Slepchenko and coworkers describes the new hybrid deterministic stochastic spatial solver used in VCell.  Schaff, J.C., F. Gao, Y. Li, I.L. Novak, and B.M. Slepchenko. 2016. Numerical Approach to Spatial Deterministic-Stochastic Models Arising in Cell Biology. PLoS Comput Biol. 12:e1005236. PMID 27959915