GOOD THING: They do go out of their way to make sure we know the full story of Osiris and how he came to die. This is important since there are a large number of comic fans who didn't read 52.
BAD THING: The problem is that after all that, they make the mistake of assuming that we've read JSA: Black Adam & Isis and know exactly why The Marvel Family is sidelined during the whole story. (For the record, I'm one of the ones who HADN'T read JSA: Black Adam & Isis and is still confused as to why Captain Marvel isn't Shazam and why Mary Marvel isn't dressed like a reject from Remember The '80s?)
The Final Verdict: One of the more interesting Blackest Night tie-ins, if one of the more confusing. The Marvel Family isn't in it, except to explain why they aren't in it. And the book rather depends upon the reader being familiar with the events of JSA: Black Adam & Isis and 52, yet only recounts the details of the later story. Good art, though. And it's not a bad read if you can get past the continuity details.