After rereading that last sentence, the whole thing just sounds absurd. Let's put aside the dead, flesh-eating super people for the time being and focus in on the major ideas of Blackest Night.
There is a major baddy in Blackest Night. Revealing his identity is really that important and no need to spoil it here. He wants to wipe out life throughout the universe and he's using his emotionless army to extinguish all feeling and life.
Rather well known heroes and villains die and become part of his undead army. It's up to the different colored corps to stop fighting amongst themselves and band together to destroy the Black Lanterns.
Some of the major DC heroes, such as Wonder Woman, get directly involved in the color ring war and it's rather exciting to see such well-known characters reimagined as ring bearers.
With black light enveloping the universe it was only a matter of time before white light rode in like the cavalry to save the day. The last few chapters of Blackest Night are a fun ride with lots of incredible fight scenes and there are some great moments as long dead heroes and villains come back to the world of the living.
The two main artists for Blackest Night were Doug Mahnke in the Green Lantern book and Ivan Reis in the main Blackest Night title. Both did incredible work and some of two page spreads throughout the series are simply gorgeous.
I haven't done a tremendous job getting across how cool Blackest Night was to read but I think it was one of more successful "events" at either DC or marvel in the last ten years. Geoff Johns is just amazing to me as a writer. His go-to technique is to reimagine a character with a long and convoluted history and make it current and exciting for today's comic audience. He spent years setting up this event and it really paid off.
There was some fluff to Blackest Night. There were way too many tie-in books that had important story elements to completely ignore them and the dead, super-powered zombie of the week story got old.
Overall, it was a pretty great event. Next up for DC is Brightest Day. I can't wait to be wowed yet again.