It might be fair to say the typical person believes that online and Internet delivery of music and increasingly, video, has reduced industry revenue. The actual impact probably has been mixed. Sales of music arguably have declined, at least in terms of physical media and “compact disc” sales, in favor of single songs sold from iTunes and other services.

But broader industry revenues seem to be a different story. If one includes live performance revenues, advertising and other revenues such as MP3 player sales, in addition to CD sales, one can make the argument that revenue generators have changed, but also have grown. In other words, there are both winners and losers.

That might strike some as an unfair and misleading way to “count” revenue, though.

The International Federation of the Phonographic Industry in 2005 estimated the global music industry to be worth $132 billion, including revenues from music in radio advertising, recorded music sales, musical instrument sales, live performance revenues and portable digital music player sales (among a few other income categories). By 2010, the IFPI estimated the market to be worth $168 billion.

But it is hard to deny that sales of “recorded music” have fallen from about $14.6 billion in 1999 to about $6.3 billion in 2009. In other words, the music ecosystem has changed in different ways for different segments of the business. Apple and other suppliers of MP3 devices have gained, while suppliers of “recorded music” have lost.

That illustrates an important fact about many changing ecosystems, including video entertainment, the mobile business, the information technology business, the advertising and the software and consumer electronics businesses. Specifically, business outcomes now are in flux.

There is an argument, for example, that from 1998 to 2010 the value of the worldwide entertainment industry grew from $449 billion to $745 billion, according to PricewaterhouseCoopers (PwC) and iDATE.

In the United States, consumer spending on entertainment as a percentage of income has continued to rise significantly over the last decade.

According to the Bureau of Labor Statistics, in 2000, 4.9 percent of total household spending went to entertainment. By 2008, the share of household spending was up to 5.62 percent, an increase of nearly 15 percent. That’s a big shift in household spending, which tends to be quite stable.

Excluding box office receipts, the film portion of the business has grown worldwide by almost
six percent over the five-year period from 2005 to 2010. Up to this point, at least, using almost any measure of revenue growth, video entertainment has grown. The big question is what happens in the future.

Many believe big changes are in store. But astudy by the Computer and Communications Industry Association suggests that the Internet has not actually cannibalized the entertainment business, the implication being that entertainment ecosystem providers should not “fear” the rise of online delivery.

The fate of the music ecosystem, though, might suggest that revenue gains and losses will be unequal. In other words, even if the ecosystem grows revenue, participants within the ecosystem still could lose. So far, some parts of the “entertainment” have been disrupted less than others. The issue is whether that will change.

By one line of reasoning, there is not much danger. In terms of global consumer spending, subscription TV services, for example, have risen with a compound annual growth rate of about six percent over the last several years (including the most recent recession), exceeding $200 billion in 2010. But there are now signs, especially in the U.S. market, of a growth slowdown.

According to several PwC reports over the last few years, the global book publishing market was worth about $100 billion in 2004 and has grown to almost $110 billion in 2010. But that was before the widespread new trend of tablet adoption, which some believe will have negative consequences for retail distributors and physical product producers. The Borders bankruptcy and stresses in the Barnes & Noble business are key examples.

Globally, the amount that consumers spend on video games for hardware, software and accessories has grown from about $20 billion in 2000 to approximately $70 billion in 2011, according to various reports from PwC, Gartner and iDATE. Of course, many would note that sales behavior is changing, with less spending growth on game system titles and more sales of casual gaming apps intended for consumption on tablets, PCs and smart phones.

The point is that, in most entertainment and communications businesses, the risk of serious change is growing, even if the ecosystems are growing, overall.