Article says pressure sensors, and also to efficiently act as a catalyst in chemical reactions requiring gold - Admittedly I'm not sure why this form of gold is superior as a catalyst.

Catalysts are not consumed. The effect is dependent on contact, so like the platinum in a catalytic converter the goal is surface area at minimum cost.

Aerogels have enormous surface area compared to their volume and chemical reactions are all about the amount of surface area engaging in the reaction.

That does imply that the gold is porous, and not made up out of chambers.

Actually, jewellery is one area this isn't useful. The end product is far too soft and would be damaged.