Brad Pitt's 'World War Z' to be a 'Bourne' type trilogy?

Pitt on WWZ set, courtest Celebuzz
An interesting tidbit emerged about the World War Z movie when Moneyball actor and producer (and likely Oscar contender) Brad Pitt recently spoke with The Los Angeles Times.

In the piece, the newspaper reveals that Paramount and director Marc Forster (Quantum of Solace) views the adaptation of Max Brooks' book not as a stand-alone feature, but as a trilogy with the "grounded, gun-metal realism" of the Bourne series. This is certainly a better approach for the expansive zombie apocalypse journal, but will the gritty action approach rob the movie of some gory, hardcore horror elements?

We'll find out next December when the movie debuts. In the meantime, here is the relevant excerpt from the article (after the jump):

Rounding out the eclectic list, he spent much of the year running from undead extras while filming 'World War Z,' an adaptation of the Max Brooks globe-trotting horror novel and the most expensive zombie movie in the history of Hollywood. 
"Like I said, I like mixing it up," Pitt said with a chuckle during an October interview on the Budapest set of 'World War Z.' "You need to make it interesting for yourself to make it interesting for other people." 
In 'World War Z,; due in theaters right before next Christmas, Pitt will play a United Nations fact-finder and family man who desperately races around the globe to determine the origins of a zombie pandemic that has toppled civilization in short order. The film is directed by Marc Forster ('Finding Neverland,' 'Quantum of Solace') and is similar in spirit to September's 'Contagion' (from director Soderbergh and starring Damon) with its geo-political bent and the aspiration to deliver social messages amid the moans and screams. 
For Pitt, the big sci-fi thriller also represents his strongest bid to have a big film franchise of his own, which might be viewed as the missing piece of his career jigsaw puzzle. Forster and Paramount Pictures each view 'World War Z' as a trilogy that would have the grounded, gun-metal realism of, say, Damon's Jason Bourne series tethered to the unsettling end-times vibe of AMC's 'The Walking Dead.'