It was actually recommended by another MNer (sorry, can't recall who) and I have just read it and am very very impressed.
Easy and interesting to read, but by no means dumbed down (writers are serious academics). It covers research to date and reviews many other forms of intervention and considers the evidence for them.
It looks at the process from the perspective of a parent, a professional and an education authrity.It's American but most of what is said holds true for the UK.
Really really worth a read.
Sense and nonsense in the behavioural treatment of autism:it has to be said