Sales rankings in the mobile sector are a bit confusing.  There's OS market share, there's smartphone OS market share, there's hardware market share, and there's smartphone hardware market share.  To make matters worse, both domestic (U.S.) and global numbers are often tossed around ambiguously.  Still there's some merit to these various numbers, if you make sure to put them in the proper context.

This week market research firm IDC published a new report looking at total global hardware market share. For Apple the report is a nice pat on the back.  The company was in sixth place last year, but this time jumped two spots, passing RIM and the struggling Sony-Ericsson to settle into fourth place. 

That performance comes courtesy to a record 14.1M handsets moved in (calendar) Q3 2010.  Shipments of iPhones almost doubled from 7.4 million units shipped in Q3 2009.  That performance looks particularly impressive given that the iPhone 4 sales were almost certainly effected by a number of quality issues, carrier exclusivity, and tough competition from Google's Android OS.

While RIM was passed, it can take comfort in the fact that it bumped its shipments from 8.5 million units to 12.4 million units, a testament to its continued appeal to business users.  RIM is currently in fifth place in total sales.

The news was decidedly worse for Nokia.  It managed a razor-thin growth from 108.5M units shipped in Q3 2009 to 110.4M units shipped in Q3 2010.  While that was enough to help it hang on to first place in sales, competitors (Apple, RIM) posted larger growth, dropping Nokia's market share from 36.5 percent to 32.4 percent.  

According to IDC, Nokia is primarily losing smartphone market share to Android.  And equally troublesome, it reportedly is losing market share (non-smartphones) to local cell phone makers in developing nations.  The company's struggles are intimately linked to the growing storm in the company's executive ranks.  The company's CEO was recently pressured to resign, and multiple other top executives have departed after the company opted to appoint its first non-Finnish CEO(Nokia is based out of Finland).

Nokia isn't the only phone maker who is struggling, according to the report.  It shows South Korea's LG Electronics posting a drop in shipments from 31.6M handsets to 28.4M in the year-to-year quarterly sales.  LG Electronics, like Nokia, has experienced recent executive turnover.  Amid its floundering phone performance, its CEO stepped down.

Sony-Ericsson similarly struggled.  The company was bumped from the top five for the first time since 2004.  The company does have a chance to recoup some of this ground, as it reportedly is preparing the long-awaited Playstation Phone for a launch early next year.  Powered by Android 3.0, this gaming-centric smart phone is virtually guaranteed to be a sales blockbuster if Sony-Ericsson can avoid the bugs that plagued some of its devices.

To add a bit of context for those puzzled why Android handset makers (e.g. Samsung, Motorola, HTC) aren't more heavily represented on this list, there's a couple reasons for that.  First Android reportedly still trails Apple in total global sales, though it has passed it in U.S. sales.  Given Android's faster growth rate it seems a matter of time before it passes Apple in total global sales. 

More importantly, though, Android's market share is fractured between several handset makers, each of which move anywhere from a couple million handsets to several million handsets a quarter.  Most of these makers haven't reached the top five in global sales -- yet -- because traditional cell phone sales continue to dominate, and Apple and RIM's sales still surpass those of any single Android-exclusive OEM.  Granted LG Electronics does make Android handsets, so Google's OS wasn't entirely unrepresented on the list.  But LG electronics' Android devices have been outsold by HTC and Motorola, so this list fails to give full perspective on the smartphone landscape.