It looks like you're new here. If you want to get involved, click one of these buttons!
When you think of GPUs, you probably think primarily of AMD and Nvidia, in some order. In desktops and laptops, they're certainly the main players, apart from Intel integrated graphics at the low end. But on ARM devices (e.g., basically everything Android and iOS), they're all minor players (Nvidia) to non-existent (AMD and Intel, though they're working on breaking in). There, the main GPU vendors are Imagination, Qualcomm, and ARM.
With their PowerVR Rogue 6 series, Imagination made some noises about how they'd support newer graphics APIs, rather than just the gimpy mobile-oriented stuff like OpenGL ES. The various mobile vendors sometimes made a big to-do about how they supported DirectX 11, but it was only feature level 9_3, which meant that as far as the feature set supported, it was basically DirectX 9.0c. On archaic architectures that lacked unified shaders, that's the newest that is reasonable to support.
But now Nvidia is pushing Kepler GPUs in tablets, and soon will offer Maxwell. Kepler already supports basically all of the latest and greatest features, and Maxwell will do likewise, while probably bringing power consumption down. That opens up the possibility of games offloading a lot more work to the GPU, which makes things more efficient all around.
But when the Nvidia Shield tablet launched, there was the question of, what games, exactly? You don't write tablet games that will only run on a handful of tablets.
But look at what the PowerVR Rogue series 6 GPUs supported: DirectX feature level 10_0 at best, basically the DirectX 10.0 that launched with Vista. The Android Extension Pack that basically adds modern graphics capabilities to OpenGL ES without filling in all of OpenGL is listed as "optional". I'm not entirely sure what that means, but if I want to know whether hardware will do what I need, I want a better answer than "optional".
With PowerVR Rogue series 7, Imagination is finally pushing a modern graphics architecture. It sports unified shaders, a dedicated hardware tessellator, and various other modern amenities. Android Extension Pack is now supported. The DirectX feature level 11.1 is listed as "optional", though that might mean, "If anyone ever decides to use it in a Windows device". Which they probably won't, unless perhaps Intel feels the need to license someone else's GPU for their own integrated graphics, as they did with Cedar Trail Atom.
Also interesting is that Imagination has ambitions of pushing a 512 shader part for consoles. For comparison, the Xbox One has 768 shaders, while the PlayStation 4 has 1152. Of course, those just launched recently, and I don't expect either Microsoft or Sony to replace them by a new, lower performance console so soon. So I'm not sure what Imagination is trying for here. Perhaps alternative consoles like Ouya? Successors to PlayStation Vita or Nintendo 3DS?
There's also the question of whether the coming Imagination GPUs will offer performance per shader anywhere near AMD's GCN or Nvidia's Kepler or Maxwell, let alone future architectures. Remember that AMD and Nvidia GPU architectures are designed to clock somewhere in the ballpark of 1 GHz; the tablet chips are severely underclocked alternatives. I'm not sure how Imagination GPUs have traditionally been clocked, but it's surely nowhere near 1 GHz. I'd be surprised if their past GPUs even reached half of that.
Regardless, it's good to see another GPU vendor trying to push GPU architectures forward, rather than living in the DirectX 9.0c era forever. It's unlikely that Imagination will push things forward anytime soon at the leading edge the way AMD and Nvidia routinely do. But more GPU vendors offering at least kind of modern architectures means that perhaps someday games will be able to use the modern APIs and hope for near universal hardware support.