I just bought an ultrabook, and VGA and RJ45 ethernet were on my short list for needed features. BTW, its slimmer/lighter than an Airbook.
That's one of the things I dislike about Apple. They get rid of ports people need simply because of their design "vision"... and then force you to carry various dongles to make up for lack of the connector.
I don't know why one would want to be forced to "rely" on wireless.
I currently have both Windows and Apple laptops in my family and I'd be happy if my Windows laptops will get lighter, thinner and screen-touchable keeping the same performance and capabilities. This trend was happening for a long time in fact. It is a good thing that it was realized by manufactures now. It also means that some bulky laptop features like DVD drive and VGA will go away and it will rely more on wireless, which I like both as a customer and a professional.
'Will Apple move to ARM?'
It already did---iPads and iPhones and iPods have always been running on ARM. I suspect that the main reason for Intel CPU in MacBooks was Microsoft Office---MS seems to be very reluctant in cross-compiling their OS/apps.
Whether it's a leadership strategy probably depends on whether you define leadership as being perceived as being on the cutting edge or simply market share. Companies can make a lot of money being competent fast followers. Some people will want to pony up the money to have the Apple branded product. Many will be willing to wait a few months and buy Android or Windows to get more choice and better prices.