Compete.com’s December US Mobile Subscriber Market Share report has been released. Of particular interest to me is the shifting sands of the Smartphone Platform Market Share. The numbers reflect the December release of the Droid by Verizon (and their heavy advertising) but not the release of the Nexus to T-Mobile which occurred in January.

I have made the point before, and this chart strongly reinforces it, that initially Android is going to take share from RIM, Palm and Microsoft and not so much from Apple. Clearly, RIM has a lot to loose in this battle although Palm perhaps has even more to loose in that their survival is at stake. Apple will soon respond with a new phone and other tactics to increase market share.

Because this is as much a battle of providers as it is phones it seems likely that Apple & Android will continue to be favored alternatives at ATT & Verizon leaving little breathing room for the current alternatives to gain or even retain market share. The Compete.com numbers:

Smartphone Platform Market Share

RIM was the leading mobile smartphone operating system in the U.S. in December 2009 with 41.6 percent share of U.S. smartphone devices. Apple ranked second with 25.3 percent share (up 1.2 percentage points), followed by Microsoft with 18.0 percent share, Palm with 6.1 percent share, and Google with 5.2 percent share (up 2.7 percentage points).