Over on the official Facebook page for Heroes of the Storm, they're sporting a new version of the logo.

Underneath it is a hidden design that one eagle eyed fan (Charles Beesley III) thinks is taken directly from Diablo. 

 I think that certainly looks like the image underneath the logo and is unquestionably Horadric. is this gaurenteed to see Deckard Cain arriving into the Nexus? No, sadly not. In fact, it might just be themed to welcome the arrival of Auriel. Which would be totally rubbish.