Abstract: The Wide Field InfRared Survey Telescope mission is the highest priority large space project recommended by the 2010 Astronomy and Astrophysics Decadal Survey, and it is expected to begin development in 2017 when the James Webb Space Telescope is nearing launch. WFIRST was conceived to conduct wide field, near-infrared surveys for dark energy, exoplanet gravitational microlensing, and general astrophysics using a moderate aperture (~1.3-m) telescope. NASA has recently approved the use of a much larger, Hubble-sized (2.4-m) telescope that was donated by the National Reconnaissance Office. A science definition team is now studying a revamped WFIRST mission concept with this telescope, including a coronagraphic instrument for exoplanet and disk imaging and spectroscopy. This talk will highlight the mission's science potential including brief descriptions of its dark energy and general observer programs with more focus on its exoplanet microlensing survey and coronagraphic imaging and spectroscopy of nearby exoplanetary systems.