Did I mention gold? There's a lot of gold involved currently. In order to open up your Void Storage vault, there is a fee of 1,000g. Once you've opened the vault, it costs a whopping 100g per item to deposit it into your vault -- and another 100g per item to remove it. With 80 slots available to fill, that quickly adds up to 8,000g just to place all your items into Void Storage. Want to take them out? It's another 8,000g.
Keep in mind, however, this is the PTR and prices may change -- although most players have so much gold on their hands by now that this could almost be considered a needed gold sink.
Check out the gallery for a full step-by-step walk-through of the Transmogrification and Void Storage process, and keep your eyes peeled here at WoW Insider for more PTR news.