The sight of 140,000 foot-weary people washing through the cavernous halls of the Las Vegas convention centre, all desperate to find the next big idea in consumer electronics, is enough to inspire a mixture of awe and terror.

A $600bn global industry of televisions, mobile phones and consumer PCs depends on the outcome of this annual pilgrimage to the Nevada desert. And while this year the eye-candy was as breathtaking as ever – from a 150-inch, 2,000lb Panasonic TV to a 3mm-thick Sony screen that costs more than a family vacation – there was a subdued but unmistakable anxiety in the air.