I'm reviewing this because I read it after the 'biography' of Matt Smith and am going to use it to compare. I believe this is a much finer example of how a biography based on a Doctor Who actor should be written. However it is hardly the finest biography I have ever read (and I've read very few).
The information is thoroughly researched and I learned facts that I would not have found by simply looking it up on Wikipedia. Much of the information I believe can be sourced from Wikipedia and if I were looking at a biography to buy I would hardly buy this. As far as insight into the writing of the new Doctor Who seasons two, three and four I would also refer instead to The Writer's Tale rather than this biography because to be honest this skimmed over the surface in a lot of ways and did repeat itself.
Compared to the biography of Matt Smith however this was a finer example of writing, featuring quotes and more succinctly informing the audience about the history of the Doctor. It also was more of a biography and was written in a highly more sophisticated manner. I felt from reading this biography that the writer was personally interested in his subject matter rather than trying to cash in on the popular movement. However the biography was hardly compulsive reading and tended to drag meaning that even as I've been racing through books they've been dragging me down with their slow pace...
However if you're interested in the star that is David Tennant I'd recommend this purely for information's sake. Although I do believe watching a few documentaries, some Doctor Who, his Hamlet production or all manner of other television performances would reveal more than this book.