Lucky for me, I only have a core set and everything for the Dunwich Legacy (and some stand-alone scenarios), so if they were to convert everything to this new format, it would be a win for me. I could see just skipping everything for the moment and just getting the two To the Edge of the Earth boxes to get a full campaign and a bunch of new investigators and cards. Compared to the old model, it saves about $40 as well overall, as long as the campaigns are of similar length. Then I could wait and see if they do re-release previous campaigns in the new format, and if not go ahead and try to get all the packs needed for a new one.
Of course, I need to actually finish the Dunwich Legacy, as I failed my first try at it. Probably going to need to bring two investigators to really have a chance.
I understand there is a revised Core set coming out at some point as well, which will probably be a great deal of overlap with the existing one, as for the new campaign formats they still say you need a core set to play, and that will need to remain true regardless of which core you have. With luck, it’s just adding more of the cards that only had a single copy in the original core set, which prompted people to pick up a second core for more deckbuilding options.