  We revisit certain aspects of thermalization in 2D CFT. In particular, we
consider similarities and differences between the time dependence of
correlation functions in various states in rational and non-rational CFTs. We
also consider the distinction between global and local thermalization and
explain how states obtained by acting with a diffeomorphism on the ground state
can appear locally thermal, and we review why the time-dependent expectation
value of the energy-momentum tensor is generally a poor diagnostic of global
thermalization. Since all 2D CFTs have an infinite set of commuting conserved
charges, generic initial states might be expected to give rise to a generalized
Gibbs ensemble rather than a pure thermal ensemble at late times. We construct
the holographic dual of the generalized Gibbs ensemble and show that, to
leading order, it is still described by a BTZ black hole. The extra conserved
charges, while rendering $c < 1$ theories essentially integrable, therefore
seem to have little effect on large-$c$ conformal field theories.
