While it's still good news that Diablo III will be available to PlayStation 4 players, Blizzard has just confirmed that the game will not feature PS4/PC cross-platform play or support for Battle.net.

In a thread on the official Battle.net forums, Blizzard community manager "Vaeflare" answered fan questions about the implementation of Diablo III on PS4. When asked about cross-platform play and Battle.net support, Vaeflare stated:

"While we think cross-platform play would be awesome, there are currently no plans to allow connectivity between PlayStation Network and Battle.net (this is pretty standard for most games that have PC and console support). As a result, the characters on your Battle.net account and PlayStation account will also remain separate. 

In terms of allowing an analog controller hookup for the PC, we don't have any plans for that kind of support right now. Similarly, since Diablo III for console was designed with a controller in mind, the PlayStation version of Diablo III will not support USB mice or keyboards."

Sounds pretty definitive, if a bit disappointing.

Earlier, Blizzard confirmed that the PS4 version of Diablo III will allow offline play.

Source: Blizzard via Joystiq