Things are going well for Apple's (Nasdaq: AAPL) iPad since last month's launch. It has sold over a million of the slick tablets, and they're being put to good use. iPad owners have downloaded 12 million applications from Apple's App Store and 1.5 million digital books.

Today the company announced its expansion push abroad. It will begin selling the iPad in nine more countries by month's end, with plans to tack on another nine countries in two months.

I'm not one to bash the iPad. I've owned a 3G model since it came out last weekend, and love it. My family has gotten more use out of my iPad in a single week than two years of Kindle ownership.

What can I say? I guess I'm not the bookworm that I fancied myself out to be.

However, before we begin crowning the iPad as Apple's new darling, let's go over a few of the reasons why it will be hard- pressed to top the iPhone as a contributor.

1. International success is no shoo-in
There will clearly be demand abroad, but will the developers show up? The two most popular non-Apple applications during the iPad's debut weekend were digital streaming apps by Netflix (Nasdaq: NFLX) and Disney's (NYSE: DIS) ABC.

Netflix remains a stateside service. It has plans to expand into one international market later this year, but it obviously hasn't secured licensing rights to offer its streams overseas. ABC may own its own content, but it is unlikely to offer its ad-supported broadcasts internationally.

Country-specific media giants may very well step up to fill the voids, but they may sit on the sidelines until they see that the iPad is a needle-moving hit on their turf.

2. The iPad won't scale down in price
Few people seem to remember that the original iPhone set early adopters back $599 during the first few months. The one-two punch of added features and huge price cuts created the brisk-selling $199 monster that AT&T (NYSE: T) is subsidizing today.

The iPad will clearly receive enhanced features with every annual update, but the prices are unlikely to budge from the $499 to $829 price points of today. There is no AT&T to fork over hundreds of dollars, because it knows it can recoup the investment in wireless charges over the next two years. The regular iPads aren't tied to wireless carriers, and the 3G model has a rock-bottom $30 monthly price for optional unlimited 3G connectivity.

In other words, there won't be some sub-$100 iPad shuffle in this product line, and that will restrict it from universal ownership. Naturally this is also an argument that one can make about the iPhone as well given the costly monthly plans, but then we get to our final point.

3. Portability matters
The iPhone and all iPod models fit comfortably in most pockets. There's a reason why athletic footwear giant Nike (NYSE: NKE) teamed up with iPad to create an integrated fitness solution four years ago. There will never be a Nike + iPad Sports kit.

Obviously you don't have to be tiny to succeed. Plenty of people lug around laptops, e-book readers, and netbooks these days. However, if an iPad takes the place of a different computing device, Apple may simply be robbing MacBook Peter to pay iPad Paul.

I firmly believe that Apple has a real winner here, and I thought this long before I became -- well -- one in a million. However, I also have to temper my enthusiasm because it will take a long time before it even challenges the iPhone to take over the wheel at Apple.

Are you one of the first million iPad owners? If you haven't bought in, will you? Share your thoughts in the comments box below.

Walt Disney is a Motley Fool Inside Value recommendation. Apple, Walt Disney, and Netflix are Motley Fool Stock Advisor selections. Try any of our Foolish newsletter services free for 30 days.

Longtime Fool contributor Rick Munarriz is loving his iPad, and he has been a Kindle owner since 2008. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. He does not own shares in any of the companies in this story, except for Disney and Netflix. The Fool has a disclosure policy.