I don't think it's just naming conventions that will factor into that. I think WotC got burned so badly by making a major break with 4E that, unless something dramatically changes (like sales drop to zero dramatic), they will want to have more continuity with the current version each time they push out a new iteration.
So we'll see stuff like the 1E/2E or 3E/3.5 transition, but those are editions where people quite easily used material from either side of the line interchangeably, although the market largely moved forward to the newest version over time.