It may be a long way off yet and many of you won’t be interested in a demo, because let’s face it, you’ll be buying the full game. However according to Blizzard they are looking at a ‘trial’ version or demo at some point.
[BLUE]We’re definitely looking into having a trial version available at some point, as we do for World of Warcraft and StarCraft II.[/BLUE]
Good news for those who may be sitting on the fence or gamers who may be completely new to the Diablo series. It’s worth noting though that StarCraft 2 was released in July and the demo didn’t appear until December so a Diablo 3 trial version could come some months after the game’s release. It’s always a good way to pull in new gamers once the initial sales rush is over.
Source: Blues: IncGamers