Blizzard representative and poster in the World of Warcraft forums Tseric recently commented on Blizzard tackling the gold selling spam that is coming in game alot of the time now...

We've been dealing with gold sellers, botters and hackers since before this game was ever released. It is an ongoing process, with each side always developing new tactics to outwit the other side.

Unfortunately, it does not appear there is a "magic bullet" that makes this all disappear. We continue to strongly address this particular area, as we always have.

We're in the works of developing more tools to address the problem of gold selling spammers and we expect to add more tools for our hacks team to use, as time goes on.

It is still an important part of the process for players to inform us of this type of action, so that we can document and build a case for removing account status from spammers.