When the MacBook Air first launched, nobody could deny it was physically impressive. Well under an inch thick, it was a visual delight to anybody who saw it. Ironically, any disappointment was saved for the owners themselves: the payoff for those market-besting dimensions was underpowered components and the tendency to overheat. Now, Apple have freshly inflated the Air with new technology, in fact just about everything down to the memory is new. Second time around, have they created the ultimate ultraportable?