Christopher,
I haven't seen the latest revisions yet, but certainly one major test would be: does it still show 10 domains (old test) or 9 domains (new test)?
I've been involved in CAE training for the past 6 years, and my overall take on the Allied Societies study guide is that it's a useful but flawed resource.
The best parts are the front material - most of which is cribbed (with permission) from the ASAE website & then better organized - and the key terms glossaries attached to the domains.
Take the practice questions with a LARGE grain of salt - it is VERY difficult to write really good multiple choice questions, and what's in the guide was prepared by unpaid volunteers, so the quality varies widely.
If you have the cash to spend, particularly if you don't plan to take one of the online courses or the Immersion Course, it's worth it. But it's not critical to success.
Elizabeth