Like the previous royal biography I read by Hourly History this was a little rough, but readable, for the most part, and probably (hopefully) a good overview.
It had a few of the same editing issues (I was wondering who the heck "Bug William" was until I realized it should have been "But William...") and there was one section with a series of Roberts and Richards, and a Rollo, that was almost impossible for me to follow, especially once we got into how Rollo should probably have been Robert I and Robert I should have been Robert II and William II's father was Richard the Good and Richard II's father was Richard the Fearless and then they throw in some more Williams besides the William the Bastard (later, Conqueror) and man, I have no idea... Some people had kids and some of them got married and one of them had something to do with Edward the Confessor and yeah... (I got stuck on this section of the book and then didn't pick it up again for 4 days!)
But anyway, eventually I just kept reading and didn't worry about the family tree (a diagram of which, btw, would have made some of this a lot easier to follow) and got on to learning about the Anglo-Saxons and the Vikings and the Normans and all the others. I have some pretty big gaps in my historical knowledge of this period, so getting a quick and dirty overview like this helped make sense of this period.
There were some pretty interesting conclusions drawn about how the Norman Conquest changed England and the language (the latter I know more about), turned England towards France and the Continent and away from their seafaring Northern neighbors, and made women's lives much worse thanks to stupid French laws.
But right at the end of the book the author mentions the Domesday Book for the first time without explaining what it was (which, isn't that very closely associated with the Norman Conquest?) and also talks about how tales about how Robin Hood has deeper political meanings around the Norman Conquest than most people see, and the story of King Arthur was changed by the influence of Norman knights --and that's it - no details! This, after Richard the Lionheart's book also failed to give me any insight into Robin Hood after mentioning it in the Introduction...
So, I did learn some stuff, but these books left me feeling frustrated. Don't mention something if you're not going to explain what you mean by it! I guess I need to go read more about Richard, Robin Hood, William, and probably King Arthur too.