"Offical" Diablo 3 RMAH FAQ

[frester]

Well, they obviously wouldnt use any official names or even Blizzard logos for that matter.. duh :P
Think about if from a business standpoint. The AH is anonymous.. so your average "ProGamerXXX_LoL" named guy could sell on that and noone knows who (or in that case, what) he really is. And noone except Blizzard could verify the identity.

It's a bit of a scary thought.

nah you are paranoid methinks... company would have to report how they got money anyway so it won't be secret forever... beside that i'm sure they can squeeze more money out of they time doing something useful...

[Sunshine]

-A cut of the purchase price will be given to Blizzard (similar to how the AH works in WoW, where each item sold has a small cut removed for AH fees)

No, this is wrong.

How is the transaction fee determined?

A nominal fixed transaction fee will be deducted from the seller for each item listed in the auction house. This fee consists of a fixed charge to list the item, which is assessed whether or not the item is successfully sold, and an additional fixed charge that is assessed only if the item is sold.

There's no "cut" as a percentage; it's a fixed charge.