This book starts well, but gets a bit heavy; still, I found it not too difficult to make it to the end. There were two themes that I found particularly attractive. First off, the whole story explores the way in which we change and adapt our personalities to new circumstances, new people: the two main characters find themselves magically transformed into an angel and a devil, and then back again, but each has also changed names and other things about themselves in presenting themselves to different countries, to family vs outsiders, to different women. It is not always subtle, but I found it very entertaining.
The second is the experience of London. I think there must be a common experience of both familiarity and alienation for all of us who encounter London as non-English but citizens of the former Empire. I've found this in a couple of other places (Memories of the Irish Israeli War, The Web of Fear) but I found Rushdie's portrayal of the immigrant experience of the Big Smoke gripping and familiar. (It possibly helps that my own family visits to London when I was growing up had a Bangladeshi edge.)
For the rest, I really enjoyed the effervescent use of language in the very first chapter, difficult to excerpt, and kept hoping it would come back again later in the book (and once or twice it did). There are lots of neat allusions - one of the main characters acquires the surname Chamcha, which must be a reference to Kafka's Gregor Samsa. Rushdie shows also a welcome sensitivity to classic sf, though his treatment of Doctor Who is less thorough.
Younger readers may need to be reminded that this book was somewhat controversial when first published. It's pretty clear who Rushdie is "really" writing about in the two extended passages set in Mecca/Jahilia and Medina/Yathrib. To say that this is not meant to be "about" Muhammad is unconvincing. (I bought the two Rogerson books partly in anticipation of tackling this one.) However, I find it fairly mild stuff; perhaps my sensitivities have been blunted by reading too much of what other people write about Catholicism.