Originally posted by ExistereIn the literal sense, yes, they absolutely exist. However, if DC is turning the dials back to the first few years of the heroes' careers, then the stories you mentioned technically wouldn't have happened yet, and therefore, wouldn't be part of the revamped continuity. Technically. (Though I'm sure they'll find ways to work bits and pieces of it in somehow.)
You reference sinestro corps, blackest night, etc. Those stories already exist, they're not going anywhere.
At any rate, if the bulk of existing continuity IS ignored when Flashpoint is all said and done, it would be a horrible decision on DC's part. I'd be all for them starting an Ultimate universe/Elseworlds sort of thing, in which the stories they tell take place in some universe within the multiverse, but still apart from the mainstream universe (with interactions, and/or large-scale events between the universes occurring here and there.) Imo, that would keep things fresh, AND appeal to a newer genre of readers, without having to retool mainstream continuity across the board. /shrug