This is your standard coffee table book. Large size, good heft, with lots of short articles and big pictures.
If you just discovered George Lucas and want to know the basics of his career, this book does a good job of that. You'll read about every movie his company, Lucasfilm, produced in its first 20 years of existence (up till about 1990 or so). It also includes movies that Lucas supported or worked on without credit, such as Body Heat. Lucas loves experimental and risky films, but believed critics would be harsher if his name was officially on the film. He also once helped the legendary Akira Kurosawa get a film financed--significant because Kurosawa was a big influence on Lucas.
Some themes running through the book... A lot of information comes from Lucas's close group of filmmaking friends such as Spielberg and Coppola. Since his early days, Lucas dreamed of filmmakers joining together to make the films they loved without the headaches that come with Hollywood. There are numerous stories here where Lucas had gotten help from others early in his career and then went out and helped others after he became successful. His Skywalker Ranch is the manifestation of that dream. Lucas proved that it was possible to make successful big-time professional movies without those meddling Hollywood executives.
What you won't find in this book: A lot of small details about every project. Most of the text is known stuff, but there is fair amount of detail that I had not read elsewhere. So it has some benefit to knowledgeable Lucas fans. You'll also not find any dirt or negativity. I was a bit shocked to read that ewoks were well-received. That just doesn't match my own recollection of events in 1983. It does quote Lucas discussing why he thought Howard the Duck failed. (It's still hard for me to understand how the man who created Yoda could follow up with that awful "guy in a duck suit" movie.)
The pictures are a mix of well-known and harder to find images. It's worth having just for the rare pics. I can't get enough of the candid shots from the movie sets. The shot of Lucas and Coppola with a Tucker car was nice. My favorite was the large shot of the Snowtroopers entering the rebel base in Empire Strikes Back (I wish the movie had more of that). And the wrap around cover by Drew Struzan is superb.
I think "Creative Impulse" is a good choice for new Lucas fans. Those wanting more should jump right into "Skywalking." And from there, the Rinzler three "Making of Star Wars" (original trilogy) books.