This book is a quick read and makes a nice companion to Flash Boys
which deals with the later period of electronic trading.
It begins with smaller traders spotting a technological edge - trading directly electronically. Levine is the technical genius for one of the firms. It then digresses onto Artificial Intelligence and Genetic algorithms used to develop better trading strategies than humans can develop unaided.
It generally good journalistically and makes for an exciting read but fails to give much of a technical explanation of why The Island system was better than others - why was its availability better? Scott Patterson also calls Assembly language Assembler, odd error and he's clearly not technical.
The book would benefit from someone that understood both the technology and the markets.
Nevertheless a good history of the origins of High Frequency trading, worth a read.