I think that Blackest night (the main series and the tie-in miniseries) are solid, but if you have a fondness for the DC universe ... IT'S GREAT!
I really appreciate that the foundation for this story was slowly laid over the entire length of this current Green Lantern series. It really brewed my excitement for the whole "Blackest Night" into a fervor. That being said, I absolutely do not feel it's necessary for you to have read the whole run to enjoy "Blackest Night".