According to new Nielsen data, not only is Google's (Nasdaq: GOOG) Android the most sought-after smartphone operating system among U.S. consumers, but recent buyers are also choosing it 2-to-1 over Apple's (Nasdaq: AAPL) iOS handsets.

The data marks a reversal for the Mac maker. Last fall, 33% said they wanted an iPhone, versus 26% for Android and 13% for Research In Motion's (Nasdaq: RIMM) BlackBerry. Today, 30% want an iPhone and 31% want an Android handset. Only 11% say they desire the BlackBerry.

More discouraging is Nielsen's survey of recent buyers:

Talk about daunting. Android's broad array of choices has made it the Windows of the U.S. mobile market, and a legitimate challenger to Nokia's (NYSE: NOK) status as top dog worldwide. Apple remains a strong yet niche supplier.

But is that really so bad? Here are three reasons why I think Apple shareholders can sleep comfortably:

  1. Apple's share of the U.S. installed base (27%) is roughly in line with its share of new purchases (25%). Android may be nibbling at iOS, but that's about it.
  2. According to recent Gartner data, smartphone sales soared 72% last year, yet still accounted for just 19% of the total market.
  3. In-Stat predicts that half of all handsets sold in the U.S. next year will be smartphones. Most of those sales will be for Android-powered handsets, but there's no indication that those sales will come at the iPhone's expense.

Unless they do -- which, again, I think is unlikely given the data -- Apple should sell tens of millions more iPhones into a rapidly expanding market, just as it did last quarter.

Do you agree? Disagree? Tell us what you think about the war for smartphone market share, the rise of the Mobile Web, and the iPhone's competitive positioning using the comments box below. You can also rate Apple in Motley Fool CAPS.

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