We already knew the Samsung Galaxy S III was gaining traction. Now we know just how big a drag it's been on iPhone sales. Juniper Research in the U.K. says Samsung sold 56.3 million smartphones in the third quarter. Apple (NASDAQ:AAPL) sold 26.9 million handsets over the same period.

Of the estimated 157 million smartphone sold in Q3, Samsung accounted for 35.9% of shipments versus 17.1% for Apple. Juniper didn't break out distinct handset sales in its press announcement, except to say that the S III accounted for 18 million -- or 32% -- of Samsung's smartphone unit sales during the quarter.

Meanwhile, Nokia (NYSE:NOK) suffered from a dearth of Windows Phone sales in shipping 63% fewer smart devices than in last year's third quarter, while Research In Motion's (NASDAQ:BBRY) 7.7 million units sold "hint at continuing problems," Juniper said.

And in a nod to the obvious, the firm advised investors to keep a close watch on Apple, which it expects to "better its sales in the fourth quarter" thanks to the release of the iPhone 5. All signs point to the U.S. smartphone market crown coming down to a tussle between Apple and Samsung.

The tablet market may be another story, even if Samsung has big ambitions in this area. The Frankenstorm known as Hurricane Sandy forced Google (NASDAQ:GOOGL) to postpone an event rumored to be the launching pad for a new Samsung-built Nexus tablet.

Yet it might not have mattered. Third-party reports already show Microsoft's (NASDAQ:MSFT) Surface tablet sold out on pre-order before Friday's launch at retail stores. Similarly, pre-orders of the low-end black and slate model of iPad Mini sold out within their first 35 hours on Apple's digital shelves.

Fool contributor Tim Beyers is a member of the Motley Fool Rule Breakers stock-picking team and the Motley Fool Supernova Odyssey I mission. He owned shares of Apple and Google at the time of publication. Check out Tim's web home, portfolio holdings and Foolish writings, or connect with him on Google+ or Twitter, where he goes by @milehighfool. You can also get his insights delivered directly to your RSS reader.

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