An investment in knowledge always pays the best interest – Benjamin Franklin
There’s no reason for me to believe that the new one will not be as useful as the 5th edition and this one’s definitely going into my collection. From the O’Reilly site: The sixth edition offers comprehensive coverage of ECMAScript 5 (the new language standard) and also the new APIs introduced in HTML5. The chapters on functions and classes have been completely rewritten and updated to match current best practices. A new chapter covers language extensions and subsets.