This was answered a while back.

Post on forums (not the Hearth) 

Use it to buy items. I believe it boosts your level meter.

You can also complete the minigame Forelnar for gold.

gold can be obtained only by posting on the forum when posting on the forum it boosts your lvl on here gold is used to buy items for your hoard

Thanks! :D

People seriously need to read the FAQ.

There's a thread on it.