I would love it if they did this! But there are a few problems that prevent them from doing so.

I can't find out where I read this to cite it so it could be something I magically made up one day but from what I remember it took the animation team at Blizzard an upwards of a year to create the short cinematic that is the intro to Cata. And that is without a story line or any type of real lip syncing with a large cast of voice actors.

If you remember, this was one of the requests fans of Square made regarding the Final Fantasy series which was hugely popular at the time. Square actually did take the plunge with Final Fantasy: The Spirits Within in 2001 and even though the brand was popular, the movie bombed at the box office(which wasn't even that bad of a movie IMO).

Not only that but the resources needed to pull the movie off were astronomical. It took over four years of development time and nearly 1,000 computers to render the entire movie. Now I know that processing power has increased exponentially since then but so has the level of detail we would come to expect from a Blizzard cinematic.

Now lets look at a company like Pixar who's movies, while extremely impressive, do not have the amount of detail we would expect from Blizzard. The movie Up took five years to create from writing to release. This is also taking into account the fact that Pixar already has the resources in place to start an animated movie like this. Blizzard would be starting from complete scratch to create an animated movie for Warcraft.

So we are looking at a six year turnaround time with Blizzard having to create an entirely new movie studio that would go to waste if the movie is not a commercial success. A filmed movie from writing to theatrical release takes on average 18 months.

So while I, and many others I am sure, would absolutely LOVE to see this done, I don't think it is in Blizzard's interest to devote so many resources to a project that may or may not be a success.