Threatened Vs Endangered, per the Endangered Species Act (ESA) - yes an important question although the answer as it applies to trade in corals in question and beyond gets wrapped up in Code of Federal Regulations (CFR) language. I'll try and give the CliffsNotes version in a moment but a disclaimer first.
My knowledge as it applies to ESA is limited to recent events and the writings of others more familiar that anyone can dig up on line with a little research. My day job involves me often interpreting and living by CFR language for a completely different area (pharmaceutical drug development) but nonetheless I DO NOT profess to be any authority on ESA language interpretation. If you are inclined to get into the details you could do a lot worse than follow Ret Talbot's blog Good Catch:
https://rettalbot.wordpress.com/2014/09/16/usfws-errs-but-aquarium-trade-still-spooked/
So what happened yesterday is probably a indication of what may come into effect in the not too distant future i.e. within a year. Really it was a misinterpretation of ESA language by US Fish and Wildlife Services of a jurisdiction currently in the hands of the National Marine Fisheries Services (NMFS) that has the corals in question listed under ESA as "threatened". Based on the threatened status USFWS falsely interpreted a clause that states "no commercial activity allowed". That clause doesn't inherently come into effect until a section 4(d) rule is issued. This is a protective regulation that accompanies the threatened ESA status when/if it is issued. That has not happened yet and as such there cannot be any enforcement against commercial activities concerning the species listed.
Note: If any of the corals had been listed as "endangered" then not only any commercial activities would have immediately stopped but ownership of the coral species would have become illegal and confiscation processes would have been initiated. Not very practical considering how many of us own and grow branching frogspawn coral.
So at the moment "threatened" status without a Section 4(d) rule means we are free to keep and trade the 15 Indo Pacific corals as we did before ESA listing. Note that Caribbean staghorn and elkhorn coral already have 4(d) ruling so you can't buy those but thats been like that for some time. Once a 4(d) ruling is issued for the 15 IP species corals however all commercial trade in these will stop. That could include aquaculture BUT here's where there may be some collaborative possibilities between the trade groups and NMFS. Section 4(d) affords latitude for doing the right thing in the interest of protecting the species. If it can be demonstrated that the aquarium industry (e.g. through managed aquaculture companies and efforts) can be part of the solution/protection of species then in theory that can be taken into account. That may be a pipe-dream and I'm not one to feel confident in the next year that we can convince the governing authorities but it is out there as a possibility.
Also if you've missed the discussion on the predicted ramifications beyond the 15 IP species then this is also very important to understand. Basically concern is that a 4(d) ruling on branching frogspawn coral would effectively stop all commercial activities (including frag swaps) on all Euphyllia corals because it gets tricky differentiating species. Likewise for other listed genus - not limited to species because of the difficulties in coral taxonomy and ID that we all wrestle with.
Oh and as a bonus - The common clownfish (A. percula) and the Banggai Cardinal fish are now also up for ESA listing.
Maybe more than you wanted to hear but everyone with even a passing interest in this hobby should at least be aware of what's going on and coming up.
