The 2012 Centenary edition has a nice preface by Hodges. It is an extraordinary biography that does justice the the quiet complexity of one of the great minds of the 20th century. One thing that struck me in particular, thinking about Hodges' accounts of, first Turing's time with Church at Princeton, and then later in Manchester working on what today we might call computational life sciences: there was a deep intellectual modesty to the man who, for better and worse, gave us the conceptual (and some of the practical) foundations of the information age.