Yay! Selling stuff for real money ingame = ok

It's worth keeping in mind that most of these advertisements tend to come from compromised accounts - it's far easier for them to use a stolen account to spam with than it is to pay for a new account to use. Once they lose access to one account, they simply move onto the next and continue the process, often recreating characters with the same names.

As always, report them. Most of the time these reports help us get stolen accounts back to their rightful owners, or at least secure the accounts until the owner contacts us.

You can also forward any websites selling in-game boosts and other services for real money via this page:
http://eu.blizzard.com/en-gb/submit/hacks.html