Time-resolved photo-electron spectroscopy (TRPES) has become one of the most widespread techniques for probing nonadiabatic dynamics in the excited electronic states of molecules. Furthermore, the complementary development of ab initio approaches for the simulation of TRPES signals has enabled an interpretation of these transient spectra in terms of the underlying coupled electronic-nuclear dynamics. In this perspective we discuss the current state of the art, including efforts to push femtosecond pulses into the vacuum ultraviolet and soft X-ray regimes as well as the utilization of novel polarizations to use time-resolved optical activity as a probe of nonadiabatic dynamics. We close this perspective with a forward-looking prospectus on the new areas of application for this technique.