Yes. Mounts, pets, and costumes (not including costumes you loot for quests) are located in your collections tab and are available to all your toons.
Consumables can be shared via the bank, but once consumed, they are no longer available (say you buy a motif and your crafter uses it- you will now need to buy or find another motif if you want more than one toon to know that motif).
A note on the mounts- while the skin will be available to any of your toons, the rider skill is what determines the speed, stamina, and carry capacity. You will have to train each toon to increase your mount speed for that particular character.
Mmm, ok sounds legit. But do you know if this counts for DLC too (such as the upcoming Imperial City dlc)?