What DirectX is, and why you will not see it in a non-Microsoft machine.

[Pemalite]

Soleron said:

Core IPC and clockspeed can be increased on phones/tablets for at least the next five years, they are nowhere near the limit. For example ARM was A8 two years ago, A9 now and A15 next year, single core performance increasing hugely each time and it will continue. We're at about 1GHz and the limit is ~5GHz

Clock rates are the frequency at which the transisters etc' operate at.

We haven't hit a "practical limit" thus far, new technologies and techniques are always being discovered which can improve how quickly a transister switches and the frequencies that they operate at. - For example, I remember reading a few years ago of a 100ghz transister.

Take the Intel Atom. - It is actually paired with low-powered transisters, these don't scale in frequency to well but they do save on power consumption.
The Core i7 series however uses transisters which scale in frequency far more aggressively, however they will and do use that little bit more power to pull it off.

Also, extreme overclockers managed to break the 8ghz barrier on the new AMD FX chips, so that 5ghz wall was effectively smashed, a few more die shrinks and maybe the 3D transisters may even improve that situation for stock clocks. (Global Foundries is also working on 3D Transister tech.)

There is allot to CPU design, more than what most people realise, you can watch how a CPU is made here (Dumbed down of course and not showing any architectural stuff.) -http://www.youtube.com/watch?v=qLGAoGhoOhU

For phones and consoles... You can have them running at 5 or 10ghz. But they are designed to be: Cheap, Small and Energy Efficient.
They will never match a proper Desktop processor that is designed to end up in systems costing several thousands of dollars with a several year fabrication process advantage, it simply cannot be done, the Cell was no exception, although it could perform some tasks incredibly quickly, but it has it's inefficiencies.

Now in regards to DirectX... Yes you won't see it on a non-Microsoft console.
However, AMD, nVidia, Microsoft and other companies "get together" about designing new features and standards that ends up in Direct X, this has a flow on effect to the hardware as AMD and nVidia release there products to comply with the standard as they have done for almost 2 decades.
The PS3's GPU might not be using Direct X... But rest assured that it's feature set is fully Direct X 9 compliant thanks to the console using an old Geforce 7 PC graphics card, which is fully accessible to developers.

The next generation aka, the PS4 again won't use Direct X, however it's graphics hardware should end up being fully Direct X 11 compatible, that means you finally get to experience Tessellation, Advanced Shadows and Shaders even without the API support thanks to the work Microsoft has done collaborating with hardware manufacturers in the PC space.
Example of Tessellation in-case no one knows:

Worthy to note, the Xbox 360 has a Tessellator (The PS3 doesn't), however it's fairly underpowered and only used sparingly like in water etc'.
Next gen should be interesting, we should finally have proper geometry on almost everything instead of Bump mapping that is used now, so bricks/rocks should have real actuall depth and not just be a flat surface, can't wait!