Looks like another "woo" site, as others here would say.
Viruses (in general) have the possibility of mutation, in fact, I wouldn't expect anything less.
Contrary to belief, it is plausible to create a "zombie", basic motor functions and reverting back to the most basic of instinct, to feed, add a little bit of rage and there you go. The gradual death of the body (despite being alive-ish) would be the biggest issue.
Even though it's plausible, that doesn't mean that it's likely and while I, personally, would love to have a zombie apocalypse, it's something that I, personally, don't believe that will happen in our life time, if at all.
I can't stress this enough..
It is impossible, not unlikely or, difficult, but impossible to predict when, where or, how a virus will mutate, and while many would love to be able to predict such an occurrence, isn't within our ability.
Sadly, a viral mutation is one of our weak spots, but this is something that could happen at any moment or, it could not happen at all, it's impossible to say with any amount of certainty.
Edit
World War Z, sadly, isn't scheduled for release until 2012 or, that's what this movie database says.