That's a Gold Saum. It's what the aquarium industry commonly refers to as the "green terror." It's a common name, and I say it isn't "incorrect" as it's the one 99% of people call a GT. So if that's what you are looking for.....yes, it is a GT. If you want to be specic, use the latin names.
A "true green terror" is a Stalsbergi. The Stalsbergi doesn't have the red/yellow/gold edging to the fins that the gold saum does. The Stalsbergi has silver edging, doesn't get as big, and has a real nasty temper (normally). It's pretty rare in the aquarium trade, and if you want one, you probably won't find it at your LFS. You'll likely have to get it from a breeder like Rapps, etc...
A silver saum looks pretty close to a Stalsbergi, but the scales are reverse, it gets bigger, and isn't mean as snot (normally).
A gold saum is the only one that has the red/yellow/gold edging to the fins. In my opinion, it looks the best, gets bigger than a Stalsbergi, doesn't have the horrible temperment issues, and is the best one of the group to keep for an aquarium hobbiest.
Basically, if you are looking for one of those monster GT's you see in the pics on this forum that have the gold/red edging to their fins.....That's it.