Transit marks the point where the New Adventures completely break with what t.v. Who would have ever been allowed to get away with, featuring on-screen sex and swearing. But it truth this doesn't now seem as radical as it was at the time, the swearing makes sense in the context of the characters and other books and torchwood make the sex seem mild. The biggest difficulty in initially reading the book is the heavy use of future slang and the constant jumping of location makes it occasionally hard to follow whats happening. But after a few chapters you get used to these location shifts and just let the slang wash over your head and realise that you are reading an excellent book.
The novelisation of Remembrance of the Daleks, proved that Ben Aaronovitch was a great writer and this book is a progression of his style to full novel length. In fact in places you suspect that Aaronovitch is really enjoying being able to tell as story without having to factor in budgets and the limits of BBC art departments. The future setting is well realised and the parrellels with the London Underground system are clever without being overdone. This is certainly Kadiatu's best appearance (and one that makes you wish she had appeared more often) and despite being possessed for most of the story, Bernice continues to show why people are still writing for her a decade latter. And the Doctor is brilliant, but you expect that by now and as for the infamous scene where he experiements with getting drunk, I can easily imagine most Doctor's trying this when there companions backs are turned and they feel like trying something new.