Obviously there are at least two differences between the two, the publishing year - the difference being around 6 years and its cover. So what other notable differences are there between the two? Is the newer one a revised edition or can be considered as such? Any other important information about the two books, like if one contains better or more information, etc? The reason I'm asking is because both of them are still available for purchase, and I'm about to make a purchase, so I need some information before I can make the informed decision.

Thanks a lot before hand :)