Full article at Blizzard link above, covers "Hotfixes, Upcoming Patch, and Ongoing Issues"; also says that due to the problems people have had staying on Bnet servers & etc that they are postponing the opening of the Real Money Auction House (RMAH) for D3, they also cover
"Battle.net®/Diablo III Security Concerns" which fits with what I have blogged already about here (includes link to Blizz to open ticket if account is hacked) & here, but below are some direct quotes of critical sections about Bnet/D3 security from Blizzards current article linked at top:
...the number of Diablo III players who've contacted customer service to report a potential compromise of their personal account has been extremely small. In all of the individual Diablo III-related compromise cases we've investigated, none have occurred after a physical Battle.net Authenticator or Battle.net Mobile Authenticator app was attached to the player's account, and we have yet to find any situation where a Diablo III player's account was accessed outside of "traditional" compromise methods (i.e. someone logging using an account's login email and password).
...we've also seen discussions regarding the possibility of account compromises occurring in ways that didn’t involve these "traditional" methods -- for example, by "session spoofing" a player’s identity after he or she joins a public game. Regarding this specific example, we've looked into the issue and found no evidence to indicate compromises are occurring in this fashion, and we've determined the methods being suggested to do so are technically impossible. However, you have our assurance that we’ll continue to investigate reports such as these and keep you informed of important updates.and
The best defense against account theft still includes smart password management (e.g. using a unique password for every site/service and keeping your password to yourself) and scanning for malware and viruses regularly, as well as following additional preventative steps found here. In the end, while no security method is 100% foolproof, the physical Battle.net Authenticator and Battle.net Mobile Authenticator app are great ways to provide your account with an extra layer of protection.
I hope that helps, you can click on the Diablo 3 Label, to see all of my Blog posts on D3, you can find that Label and select others in the Labels cloud at left side of the Blog. Every blog post will also have Label(s) at bottom left of post.