Trista Rehn and Ryan Sutter from 'The Bachelorette' ride on a float during the 115th Annual Tournament of Roses Parade on January 1, 2004 in Pasadena, California. - 

Update, 10 a.m., July 31: The government is reporting GDP grew at a rate of 1.7 percent from April to June, beating analyst expectations.

Original story: The Commerce Department revises the items it includes in its Gross Domestic Product estimates on Wednesday. From now on, things like research and development, books and box office hits are going to count in our overall economic picture.

Say what you will about the show "South Park", but as a long-running series, it's a vital part of our future economic growth. Just ask Alexander Field, an economic historian at Santa Clara University.

"Creating a blockbuster film or television show that will continue to earn royalties or go into syndication in the future is a valuable asset to our economy," Field says.

Another big change? Research and development -- say, when a business invests in a new drug or computer technology -- will now count toward GDP. That's a good thing, says Melissa Thomasson, who teaches economics at Miami University.

"Research and development are things that hopefully make us more productive in the long run," she says. But she doesn't think the bump in GDP from adding entertainment is as valuable, "especially to the extent that we're measuring royalties on something that's already going on," she says.

The U.S. Bureau of Economic Analysis says it'll get some of that information from trade sources, and it will extrapolate some of the rest, going all the way back to 1929.