Kripparrian and Krippi Hardcore Diablo Inferno World First Kill
It's everywhere on forums, Kripparrian just defeated Diablo in Inferno difficulty in Hardcore mode! This is, as far as we know the world first kill but Bashiok hinted that it might not be the case on his Twitter Account.
Update: Bashiok has confirmed they are indeed the world first Hardcore Inferno Diablo Kill (source)
Congratulations to the Kripp/Krippi duo for this nice achievement.