comScore marketshare data reveals Amazon's Kindle Fire accounted for 54.4 percent of the Android tablet market in February 2012. Full details at Neowin.
Why is this significant? Well, the Kindle Fire doesn't use Android in the strictest sense. At its heart, the OS is based on Android 2.3 Gingerbread, but Amazon ripped out just about everything that it could. More than just the kind of custom user interface overlay that you'd see on other Android devices - such as HTC's Sense UI or Samsung's TouchWiz - the Kindle Fire user experience is built entirely around Amazon's own services, actively restricting and excluding access to services like Google's Play Store for apps and music.
As a result, Google's services simply don't get a look-in on the Kindle Fire, which instead features Amazon's own offerings - buying apps, browsing the web, watching video, downloading music, buying e-books and all the other stuff you might want to do on your Fire, is designed first and foremost around what Amazon has to offer you.