Very Good Book!!!
I have the Learning ExtJs book also.
Ive been in programming going back over 25 years. Started out on the IBM System 34. There were no servers, PC's yadayadayada back then. I program almost exclusively on the IBM System i (AS/400), but ExtJS is by far the best thing to come along in my experience. It will change the System i market from top to bottom.
Thank You Folks for all your efforts. Keep up the good work.