So, we'll still have Duplicate and Off Topic, but pretty soon our four other closevote reasons...
Not A Real Question
...will be replaced by three new alternatives...
Unclear What You're Asking
I think ELU might have a bit of a problem there. I've just realised our current FAQ doesn't actually define GR - but I thought it used to, and don't recall any debate here on meta about removing it.
ELU gets a lot of really basic questions from non-native speakers, many of which are closed as GR. Presumably we'll need to change the FAQ to justify saying they're OT instead now. I'm assuming we can't just say they should go to ELL without saying why they can't stay here, and I'm not sure it's possible on SO to closevote as Belongs on XXX while XXX is still in Beta.
Anyway, it looks like TPTB don't endorse whatever we thought General Reference stood for, so we either have to bite the bullet and allow questions like the meaning “off” (sic), or we need to decide whether the site really is for linguists, etymologists, and (serious) English language enthusiasts.
Personally, I think we should include under Off Topic a sub-category called something like Common knowledge among Anglophones (effectively, the old General Reference).
I don't really have an opinion on the demise of Too Localised - most times when I've closevoted for that reason, I've been overruled (or not supported) anyway.