AMD hasn't really been a company that can become a "leader" in new markets (perhaps with the exception of APU's), either because they lacked the CEO's with vision, or because they've never really had enough money to "experiment" with new types of products for new markets.
I remember when their former CEO said a couple of years ago that they didn't want to enter the mobile market, and instead they will "wait and see" what happens. That was their exact attitude about netbooks, too, and only years later, almost at the end of the netbooks as a market, they finally released some chips for netbooks. But at that point Intel was already dominating the market, and nobody really cared about netbooks anymore, as they were starting to shift to tablets such as the iPad.
Then AMD said the same thing about Android tablets, and it looks like they still mostly care about Windows 8 tablets and laptops even now, but considering Android tablets sell more than iPads now, while Windows 8 tablets haven't done so well so far, they seem a lot more willing to give them a try.
The question now is if Android OEM's are actually interested in using their chips. Unlike Nvidia who saw the mobile market booming in the future, and decided to make mobile chips for it, and build a brand and relationships with Android OEM's, AMD hasn't done that, and it has to start almost from scratch here. So not too many OEM's will be interested in using their chips anytime soon, and they'd rather use the tried and true ARM chip brands they've used so far, that should be more energy efficient, too.
AMD has three "Temash" chips for the tablet market: a dual core 1 Ghz A4-1200 chip that draws 3.9W of power, another dual-core 1 Ghz A4-1250 that draws 9W, and a quad-core 1.4 Ghz A6-1450 chip that draws 8W, and a Radeon 8250 GPU with a 400 Mhz clock speed per GPU core.
It remains to be seen how competitive these chips will be with ARM chips such as the Exynos 5 Octa and Qualcomm S800 by the end of this year, and if OEM's decide to use them in Android tablets.