It would probably be easier to list which dead characters aren't coming back as Black Lanterns. If I had to guess, maybe Jor-El is safe, if only because Krypton's explosion probably didn't leave a body behind. Everybody else? They're all fair game. (And honestly, I'm not all that sure about Jor-El either.)
Four heroes have already been confirmed as rising from the grave as Black Lanterns. The most prominent is probably J'onn J'onzz, the Martian Manhunter, whose murder was one of the key opening acts of Final Crisis. The original Aquaman, whose status has been more than a little confusing in recent years, is the other iconic Justice Leaguer who has returned from the grave. Ronnie Raymond, the original Firestorm, is also coming back, which hopefully will make up for his utterly throwaway demise in Identity Crisis.
But arguably the most intriguing resurrection is that of Kal-L, the Superman of the pre-Crisis Earth-2 who perished in Infinite Crisis. For all the silliness that comes with the multiverse (particularly the multiverse that predated Crisis on Infinite Earths), that's still the Golden Age Superman we're talking about, the same character who began the entire superhero genre over seventy years ago. Here's hoping he gets a role and final fate worthy of his status as the original superhero.
After that, almost anybody who has ever died in the history of DC Comics could make an appearance, and I can pretty much guarantee there will be at least one full-page battle scene crammed with impossibly obscure cameos. For what it's worth, the voice of Death in Green Lantern #43 singles out a whole bunch of dead characters, all of which are now pretty much guaranteed to appear. These characters include, along with the previously named heroes, the original Aquagirl, the Golden Age Atom, Ralph and Sue Dibny, the original Captain Boomerang, Ted Kord, Maxwell Lord, the Freedom Fighters Phantom Lady, Black Condor, and Human Bomb, the Psycho-Pirate, Vic Sage (the original Question), Jean Loring, Arthur Light, Deadman, Terra, Wesley Dodds, Jade, and Jonathan Kent. The inclusion of Superman's recently deceased father makes one thing abundantly clear - Blackest Night is not going to shy away from bringing anybody back. By the way, there's actually one more name on that list, but I'll come back to that in a moment.
Then there are all the dead Green Lanterns. Considering Hal Jordan's origin story is inextricably tied up in the death of his predecessor, I think it's safe to say he's going to face off against a Black Lantern Abin Sur at some point in Blackest Night. Then there's the reunion of John Stewart with his dead wife Katma Tui, an event already foretold by the recently reformed villain turned Star Sapphire Corps member Fatality. There are plenty more, including Tomar-Re, Ch'p, and Jack T. Chance, although none of them have quite the same impact as the likely returns of Abin Sur and Katma Tui (although don't underestimate the emotional heft of a Black Lantern super-intelligent chipmunk).
The big question, at least as far as I'm concerned, is how Blackest Night is going to handle Bruce Wayne, the final name in Death's list in Green Lantern #43. In fact, the cover of that issue prominently feature's Bruce Wayne's tombstone (which is inaccurate, as Batman is buried in an unmarked grave). Blackest Night #0, the preview issues released on Free Comic Book Day, ended with Black Hand, the newly minted herald of the Black Lantern Corps, unearthing Batman's grave. There's a lot there to suggest Bruce Wayne will be involved as a Black Lantern, but I'm frankly unconvinced.
After all, Final Crisis ends with the pretty clear implication that Bruce Wayne is still alive somewhere, albeit most likely lost in prehistory. To be sure, Superman recovered a skeleton in the Batman costume at the end of Final Crisis, but it's anyone's guess whether that skeleton is actually Bruce Wayne in any real sense. Besides, Batman is one of the two biggest characters in the entire DC universe (and arguably one of the three biggest superheroes in all of comics), so it's a little hard to imagine his return won't have its own event devoted to it. There have also been no concrete indications that Bruce Wayne will be a Black Lantern, and he's conspicuous in his absence from the solicitations for the Blackest Night: Batman mini-series. (I'm also not sure about Ted Kord, who I'm pretty sure was quietly resurrected in Booster Gold but hasn't yet revealed this to the world at large.)
In any event, it's probably fair to say that, with the possible exception of Batman, every major dead character will be back as a Black Lantern, and most of the minor ones too. And if there's any chance a character's return would be heartbreakingly cruel to a living superhero, I think it's a safe bet Geoff Johns will find a way to make it happen.