According to a new report from market research firm, Canalys, 50% of all computers sold in 2014 will be tablets (285 million of them, to be exact, which is more than notebooks), and 65% of those will run Android. That means there will be ~185 million new Android tablets sold in 2014, which is actually slightly more than the total amount of tablets being sold in 2013 (182 million).
It used to be that the iPad was considered the "iPod of tablets", meaning that iPad will always have a very dominant lead of say over 80% of the market. But Android proved once again that it can rise up in tablets just like it did in smartphones (people were also pretty skeptical about Android phones beating iPhone in the early days).
I've never believed that theory, because unlike in the MP3 market there was never really an "ecosystem" of "other" MP3 devices that could help beat iPod's ecosystem. Plus, the MP3 market was a lot more about the hardware than it was about the software. In the mobile market people want hardware, but they also want apps and a good operating systems. That makes it much easier for other companies that aren't Apple to adopt an operating system like Android, that they can all use, and help grow its market share.
As such, Android's domination in tablets, was really just a matter of time, unfortunately being slowed down by Google themselves, who seeded in the minds of developers the idea that they don't need to create tablet optimized apps, because their phone apps will run just fine. That really kept Android behind iPad tablets for a long time, and it's only now beginning to beat it in market share, as more developers have started optimizing their apps for Android tablets, too.
Google has also just begun to outright force developers recently to develop tablet apps, by calling their apps "phone apps", and by showing tablet users only tablet apps by default (with a few, exceptions such as Facebook and Twitter, which don't deserve to be called tablet apps).
Now that Android is poised to dominate the tablet market going into 2014, perhaps we'll see Google try to dominate the PC market, too, with an Android 5.0 version that can be taken seriously as a "Windows alternative" for work-related tasks, and that is more optimized for using it as a PC operating system (works well with a mouse/touchpad, has a more advanced real-time multi-tasking, etc). But that remains to be seen for next year.