When it comes to storing most of our online entertainment, Google (GOOGL 0.49%) and its Drive file system isn't top dog. Neither is Microsoft's (MSFT -0.16%) SkyDrive or Amazon.com's (AMZN 0.49%) Cloud Drive. The winner? Apple (AAPL 0.08%), says a new report from Strategy Analytics.

The survey asked respondents which digital locker services they use to store music or video. iCloud and iTunes topped the list with 27% using Apple's services. Surprisingly, Dropbox ranked second, two percentage points ahead of Cloud Drive.

Source: Strategy Analytics.

Whether or not this is the first time anyone's taken a serious look at the "entertainment cloud," I think it's fair to say that -- up to this point -- we've largely overlooked Apple's growing presence online. How we could not? We're too busy covering efforts by Google and Microsoft to win users to their respective cloud productivity suites.

Let's take a break from that back and forth for a moment and consider a few numbers not included in the Strategy Analytics report, but which reflect the Mac Maker's increasing influence:

Source: Apple.

Imagine if only a third of them were backed up to iCloud. I'm almost surprised Apple doesn't possess a greater share of the entertainment cloud. At the very least, I suspect some of its $140 billion fortune might go to building an overseas data center for serving the increasing number of iOS devices in use in non-U.S. markets.

Put simply: The cloud is expanding fast but, if the data is to be believed, not nearly as fast as iCloud.