Simple : Cost.I don't get why they can't put a faster CPU in the m11x.
The M11X already costs close to double the price of the other 11.6" CULV machines.
The Sony Vaio Z competes in a completely different market, at twice the cost of the M11X. Of course it's thinner and lighter - you'd expect nothing less at that end of the market. There's no logic in trying to compare it's specs to the M11X - with double the budget, it's quite obviously going to offer some improvements.The Sony Vaio Z has a thinner chassis, 330m, a regular CPU (35W) and still has a decent battery life, not to mention it's more than a pound lighter.