I thought Blackest Night was pretty terrible (it was really, really repetitive), but if you like Johns' GL you might like it. But then, I liked Johns' Green Lantern a lot during and immediately after the Sinestro Corps War, too. That was pretty cool.
I've avoided buying every event at DC since Infinite Crisis (an OK mess, substantially better than Crisis on Infinite Earths, which is probably the worst comic no one has anything bad to say about that I've ever read, but IC suffers badly from Johns' inability to write humans qua humans, as opposed to plot devices in costumes; the Day of Judgment and Villains United tie-ins are, however, both extremely awesome, and really justify IC's existence all on their own; and I did read Final Crisis, but am very glad I didn't pay for it).
I'm not sure I've even read more than a dozen Marvel comics at all since Civil War. Although I actually liked Civil War itself quite a bit, I've rather disliked pretty much everything since then, and the one thing I thought could have been cool in the long run, Spider-Man's unmasking, obviously went away... from a distance, Secret Invasion, Siege, and Fear Itself (did I miss one?) have just seemed awful in every way.
If you go back a ways, Jim Starlin's Infinity Gauntlet/Infinity War/Infinity Crusade is well worth reading, particularly if you like space opera--and anything with Starlin and Adam Warlock beats Johns and Green Lantern with a stick, I'm just sayin'.* Indeed, I'm literally alone in thinking this, I'm sure, but Infinity War is the best comic Marvel ever published. Ron Lim is also possibly the most underrated artist I can think of. A spare descriptive style and clear storyteller, obviously a fast penciller, excellent with crowd scenes, and with a lot of Perezism in his panel compositions without approaching the Unreadable Nonsense Zone.
I also liked X-Tinction Agenda. Remember that, and I owe you a coke.
Valiant's Unity crossover was also really, really, really good. Indeed, everyone should go back and read the first two or three years of Valiant--all of it, every series, no kidding. It's good for you.
*In fact, while it's non-event related, but if you ever get a chance to read the 70s Warlock stuff Starlin did, take it. If nothing else, it's formally innovative stuff, but more importantly it's damn fun and it's some of the headiest mainstream comics ever got--I'd say it's at least as weird as Grant Morrison's median,and far more earnest in its weirdness.
