It's a full reprint of EATCT, with extensive notes and extra photographs by Ortiz. There are a few modifications that Ortiz makes to some of the techniques. It's a lot easier to learn from this than the original.
Sparejoker have you read revelations? Versions annotation of erdnase? I'm considering buying it... And would be interested in your opinions if you have read it.
The only Vernon I've read is Inner Card trilogy and his contributions to Expert Card Technique.
I'm not an Erdnase fan per-se, I just bought Annotated Erdnase becasue I'm an Ortiz fan (and he sometimes references techniques from it fo some of his routines).