Microsoft CEO Steve Ballmer gave the keynote at CES in Las Vegas last night. It was a polished performance and everything worked, but was short on vision or any immediate answer to the twin forces of Apple iPad and Google Android which are squeezing out Microsoft in the mobile world – smartphones and tablets – which currently forms the centre of attention in personal computing.

That said, CES stands for Consumer Electronics Show; and Ballmer did a good job showing off how well Kinect is performing, claiming sales of 8 million already. He showed more examples of controlling Xbox through speech and gesture, and said that Kinect is also boosting sales of the console; clearly it is now taking it beyond the hardcore market of first-person shooters.

We saw some fun new Windows devices, such as Acer’s dual-screen Iconia laptop.

There was also a demonstration of the updated Microsoft Surface which now runs full Windows 7 and does not require hidden cameras, so that it can now be used in more scenarios, such as for interactive digital signage.

All well and good; but what about mobile? We got a Windows Phone 7 demo, but no sales figures, nor any mobile partners on stage; I’m guessing they are too busy promoting their new Android devices. Ballmer did say that the phone is coming on Verizon and Sprint in the first half of this year. Application availability is improving, but how will Microsoft win attention for its smartphone? My local high street is full of mobile phone shops, none of which even stock it as far as I can tell. There is a tie-in with Xbox Live which may help a little.

The problem though is that Microsoft does not seem to be wholeheartedly behind the Windows Phone 7 OS, which is based on Windows CE with a new GUI and Silverlight/XNA runtime for applications. Rather, Microsoft is signalling that full Windows is its future mobile operating system. At CES it announced Windows on ARM, the processor of choice in mobile, and during the keynote we saw the next version of Windows (though with the Windows 7 GUI) running on various ARM devices.

The power available in new System on a Chip packages like NVIDIA’s Tegra 2 leaves me in no doubt that full Windows could technically run on almost any size of device; but that does not make it the sensible choice for all form factors. Note also that while it was not mentioned at CES, NVIDIA has said that Tegra 2 is optimized for Android.

Microsoft could plausibly have released a tablet based on the Windows Phone 7 OS, which is built for touch control, this year. Instead, it will be at least 2012 before we see a Windows 8 tablet, and we are taking it on trust that this will really work nicely with touch and not need a stylus dangling at the side. By then Apple will, I presume, be releasing iPad generation 3.

Putting this in a developer context, what is Microsoft’s mobile development platform? Silverlight and XNA? The full Windows native API? Or HTML 5? Each of these is very different and it seems to me a muddled story.