Cosmological reionization in LCDM models with and without a scalar field

One would not have expected just a few years ago that we could observationally start probing the reionization process in the redshift range 6-30. This is indeed extremely exciting, because we are in a completely uncharted water. I will review some of the latest developments on cosmological reionization and suggest, in a somewhat more personal way, that the universe may be reionized twice in order to paint a picture that is consistent with all observations, including SDSS quasar observations, WMAP CMB experiment and Lyα forest observations. Further suggestion is made in the context of the LCDM model with a scalar field to promote early structure formation.