There won't be any voice-chat support at launch as the studio wants to make sure it works perfectly. There are also no plans for a higher resolution pack of textures - no 'ultra'.
Diablo has never been much about the graphics but still it's always nice to have some eye candy. Adding an ultra setting wouldn't make any difference said Community Manager.
A new skill system is on the way for the beta with the next patch bringing a number of changes to character classes. An expansion to Diablo III is possible, mused Bashiok, and a midnight launch will be supported by a digital download likely available the very moment it's officially released.
Does a 4 player co-op limit bother you, video gamer? Do you always play it alone?