The book could certainly better fulfill its role as research tool if the publishers would sponsor an updating of the notes and citations; now that everything has been published and republished by presses like Fischer and Suhrkamp in Germany and by the likes of Continuum, Columbia, Harvard, etc., in the English-speaking world, Jay's opus might be more helpful were it not to insist on citing the original issues of the institute's journals, to which most of us simply don't have easy access.
That's a small bone to pick, though, with such a thorough book. Jay's chapter on the philosophical roots of critical theory moves quickly but surely (despite the occasional dependence on disciplinary argot that may slow down readers not steeped in the vocabulary of "isms"), providing a crucial backdrop to his reading of the Frankfurt School's entire intellectual contribution. This chapter grounds Jay's book safely, and the subsequent chapters make good on this very promising start.
"The Dialectical Imagination" is sure to remain the best available introduction to the thought of the Frankfurt School on the whole. I cannot recommend it highly enough for those interested in the history of philosophy in the 20th century, in radical politics, or in developments in literary theory.