If they work together we will definetly see most of the titles on that list.And that sound as a good news to me
Nglide doesn't own the licenses to those games do they? They just have a wrapper that allows for better game emulation in the case of 3DFX games.
Them showing up on GOG would still require the publishers go-ahead. Although yes, if some of the publishers currently signed had games that wouldn't work without this I'd imagine they'll start showing up.
So at the moment GOG uses Dosbox, ScummVM, NGlide at least to work their magic for us :)