I read a book at work discussing how the left side of the brain handles math and the right side handles creativity. In most roleplaying games, for example, when a die is rolled the left side will see the number produced and compare it to what it already known about both dice and numbers. Ironically, most of us will link dice to board games first, because most of played board games before RPGs, and then switch over to applying the result to RPGs.
If the symbols for the new Warhammer dice become intuitive, however, your left side will kick off. The symbols don't compute to anything known. The right side of the brain will kick in, helping the left side determine what the symbols mean. This use of the right side will actually facilitate more storytelling (assuming the symbols are easy enough to consistently interpret) because the right side of the brain will be involved in every action rolled.
I'm not a scientist or a mathematician, but I can see how this could really help storytelling. By contrast, I'm playing D&D 4E and everything is highly analytical: lots of adding and sorting added to which is the flat D20 roll used all the time. It really distracts me from concentrating on and telling the story.
Warhammer 1E and 2E wouldn't detract from storytelling; the results aren't nearly as complex as in D&D 4E. But Warhammer 3E might actually truly enhance the story, at least according to the science I've read (and hopefully somewhat understood), because the right side of the brain handles both interpreting symbols and telling stories.