
Originally Posted by
Telefrog
Through a few contacts in security firms. These are guys I know and trust, so I don't think they are steering me wrong. They're seeing a lot of activity in various groups that indicate that they are gearing up to take on the RMAH and step up Battle.net account stealing. Of course, they can't be definitive about any of it, but better safe than sorry when it comes to your online accounts.
Besides, as stusser points out, WoW accounts are already high on the target list for these dudes. Logically, the opportunity to directly access money through D3 accounts will make them even more high-value targets.
The authenticator is free for iOS and Android users. Shipping is free if you buy the physical device from Blizzard. I can't think of a reason to not have one.