As of 2:57 PDT, only about 2 hours after the last screen update, and with the opening ceremony for WWI well underway, the splash screen for blizzard.com and other associated sites has changed to a flash file. We're expecting it change over any second now, and will update this post when it does.
It is official, everyone. Diablo 3 is coming our way.
Gallery: June 2008 splash screen speculation