Yes, and no. Most(?) pebble bed reactors have used triso style fuel (there was a similar earlier fuel type called biso, don't know if any reactors using it were

Yes, and no. Most(?) pebble bed reactors have used triso style fuel (there was a similar earlier fuel type called biso, don't know if any reactors using it were ever built), but triso fuel can be used in other reactor types as well. And yes, triso is pretty cool tech. Like the article says, it can withstand exceptional temperatures without any fission products escaping.