Within an Interview with the online gamemagazine gamedaily.com, Blizzard’s vice president of game design Rob Pardo, implies that “a new Warcraft RTS will be “one of the ideas on the table after StarCraft 2 ships”.
The complete Statement, applying  to Warcraft 4:

“Yeah, of course there’s a chance,” he confirmed. “The way that we develop things, each […]

Needless to say, that there are no real Warcraft 4 trailer existing at the moment.
But nevertheless we’ve collected some fan made trailer and movies. Some are professional and pretty, some are funny and some are crappy.
However, take a look at our Warcraft 4 trailer section.
If you have another selfmade or found trailer, feel free to […]