When Sony Ericsson CEO Bert Nordberg claims a 17% share of the market for Android smartphones, it's easy to dismiss that claim as crazy or misinformed. After all, the only Android phone available from the Sony (NYSE: SNE) and LM Ericsson (Nasdaq: ERIC) joint venture is the originally promising but now underwhelming Xperia X10. Even that model sells only through AT&T (NYSE: T) in the U.S., which is loath to promote any smartphone other than its golden goose, the Apple (Nasdaq: AAPL) iPhone. There's just no way this phone outsells nearly every Android phone on the market.

But then, you're forgetting about the world outside U.S. borders. Sony Ericsson isn't huge domestically, but remains a large presence in market geographies like Europe and Asia. Specifically, the company expects China to become its largest market "in the next four to five years."

China Unicom (NYSE: CHU) and China Mobile (NYSE: CHL) get Sony Ericsson models we've never seen here in the States. Most of them would not be compatible with the network technologies used by AT&T, Verizon, and the other majors. This hides their sales from the view of many American investors.

The ongoing move from making untold millions of value-priced, basic cell phones to building higher-ticket Android smartphones is working out rather well for Sony Ericsson. Its average selling prices are on the rise, and Nordberg claims a 4% global share of the total cell phone market by volume, but a 7% share when counted by dollars.

So it all comes down to how you count your numbers -- global or local, dollars or units? I can see how at least one of those calculations shows Sony Ericsson in second place with a 17% market share, when defined just so. Should Apple, whose largest market is in the U.S., be scared of this rising rival? I don't think so.