Apple has posted a downloads countdown page on its site as it approaches 10 billion apps downloaded. This year marks the App Store’s third birthday, so that’s an average of over 3 billion app downloads per year. iTunes took eight years to reach the same milestone.

What makes that figure even more interesting is the fact that just last year, Apple celebrated the 10 billionth download from the iTunes Music Store in similar fashion. That milestone came a full eight years after the debut of the iTunes store, which makes for an average of just over 1 billion downloads a year.

That’s six years difference in how long it took each store to reach the 10 billion download mark. However, it’s easy to see why the difference exists; there are millions of iOS devices out there, and since there are a whole load of free apps available, that’s got to account for a large percentage of those downloads. Whereas a large proportion of the App Store is free, only a very small minority of the iTunes Music Store offerings can make the same claim.

There’s also the fact that a lot of people get their music from sources outside of Apple, something which isn’t possible to do with apps without jailbreaking. People new to Apple devices likely already have an established music collection, but someone who’s never had an iOS device before won’t have any apps at all, making them more likely to download apps than music.

While Apple celebrates 10 billion downloads, HP-owned Palm is getting excited about having surpassed 100 million downloads from the webOS store. Palm may not be an iOS competitor on the level of, say, Google, but the discrepancy still says a lot about the app gap between Apple and the rest of the market.

Whoever downloads the 10 billionth app on the App Store is up for a $10,000 iTunes Gift Card, so hit up that Top Free apps list and get to it. If you’re interested in finding out how much you’ve contributed to those download numbers, you can use Geoffrey’s method for determining your yearly app spend to track and tabulate your total iOS app downloads.

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When that number does hit 10 billion (as of this writing, it was almost at 9.9 billion), one lucky iTunes customer who actually makes the 10 billionth purchase could win a $10,000 iTunes Gift Card. That’s a lot of songs, TV shows or even apps, depending on what you fancy. Especially if rumors prove true and TV show prices drop to just a dollar. And at the current pace of around 100 songs per second, it will be just under two weeks until that milestone is hit.

Apple took the opportunity to also toot its own horn, which is only fair considering it’s hard to overstate the impact iTunes has had on the music industry:

iTunes changed the way you buy music, making songs and albums available for download, day or night. Seven years later, we’re about to celebrate our biggest milestone for music, yet — 10 billion songs downloaded. Buy a song, and if it’s the 10 billionth download, you could win a $10,000 iTunes Gift Card.

Viewed over the long term, hitting the 10 billion downloads-mark so soon after the it hit 3 billion (July 2007), a number which took three years from the initial launch of the iTunes store, Apple is doing very well. Recent developments, however, have had a negative influence on iTunes music sales numbers. Specifically, I’m talking about the new deal Apple worked out with record labels that saw prices for some bestselling music jump to $1.29 per song from 99 cents.

Since then, digital album sale growth has been steadily on the decline. According to AppleInsider, the second quarter of 2009 saw 11 percent growth in digital sales, while the third only saw 10, and the crucial fourth quarter — which included the 2009 holiday season — saw only 5 percent growth. Sure, it’s still technically growth, but that rate of decline has got to be making both Apple and music industry executives nervous.

For its part, Apple is probably just content to let the music sales slow so that it can go back to record companies and say “I told you so” regarding the effects of the price flexibility required by the labels in exchange for DRM-free tracks. Customers could actually come out on top if sales continue to trend downward, since the industry might be forced to try going back to a flat, 99-cent-per-song-downloaded rate, a move Apple would no doubt support.

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Apple likes numbers, and shoving said numbers in our faces every time they reach a milestone of any kind. To celebrate the App Store’s first birthday, the company’s got a suitably huge figure to brandish: 1.5 billion. That one, five and eight zeroes indicates the number of iPhone apps downloaded within the store’s inaugural year. It’s an impressive number on its own, but it becomes even more impressive when you recall that it was only a little over two months ago that Apple hit the 1 billion-mark.

That’s half a billion downloads in around two and a half months. To say iPhone 3.0 and the new 3GS hardware probably had an effect on app downloading volume would be a gross understatement. A cursory and very unscientific examination of Twitter at the time of the official release of 3.0 saw a massive surge in interest surrounding the App Store, as people frantically shared and searched for any news of what the first push-enabled apps would be. And then probably downloaded those apps in droves as they came out.

As is now becoming standard again for Apple press releases, the official word from Cupertino includes a (rather bland) quote from returned CEO Steve Jobs, who had this to say:

“The App Store is like nothing the industry has ever seen before in both scale and quality,” said Steve Jobs, Apple’s CEO. “With 1.5 billion apps downloaded, it is going to be very hard for others to catch up.”

Basically, Jobs is reiterating what tech pundits, analysts and bloggers have been saying since Apple’s rivals started introducing their own applications stores. Nice that he at least sounds sporting about it, almost like he’s issuing a challenge.

For more info on the recent massive uptick in App Store downloads, including a lovely chart to show you just how Apple managed to amass so many downloads in such a short period of time, check out CNN’s Fortune blog post about the press release. As they rightly point out, this meteoric rise can’t continue forever. The question is, when and where will it end?

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Founder Matt Mullenweg has now blogged about the deal: what ‘Act II’ means for Automattic; how his company got here; some of the lessons he learned along the way. You’ll identify with the entrepreneurial tale:

“In 2005 Automattic was small. Through some miracle I had convinced Donncha O Caoimh, Andy Skelton, and Ryan Boren to leave their safe jobs, join a company with almost no money in the bank run by someone with no experience, and whose core idea was to give away and open source all our core IP. There were more questions than answers. Would a hosted version of WordPress move beyond the geek appeal the OS project had? How would the virtual company with no office work? Could we develop a service alongside an OS project without screwing both of them up? Should I raise money? Most importantly, would it scale?…”

Some of the answers to his questions were “hard-learned,” Matt writes. Aren’t they always? Which is why there is wisdom to be taken from Matt’s experience. Read his full post here.

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