I don't believe Apple would add any price to the price of the MBA to include the 3G/4G/LTE chips. If it costs $15 per part, I would assume Verizon would just go ahead and front the cost for it and pay Apple a percent of service revenues.
I was surprised Apple charged $129 for the iPad's 3G, but that is such low cost for AT&T service ($30), that Apple isn't getting a percentage of the 3G service revenue. Apple is making an extra $115 on the iPad by selling a 3G iPad over non-3G iPad.
If there was a cost added to the MBA, Apple would have multiple versions just as it does with iPad. I just think there's a point where Apple has to let Verizon into the party. Apple would move forward with a 3G/4G/LTE MBA first and if it's a successful model introduce the tech into the other Mac notebooks too. One thing that concerns me is the antenna with the aluminum. I don't want a plastic black strip across the lid to allow 3G reception.
ThinkDesign - I think there are many ways an MBA can be introduced at WWDC.
I think Apple would use the MBA and WWDC to introduce the "next level" of where Macs are headed. 4G/LTE (backwards 3G compatible) Verizon could be tested on the MBA and provide an added level of revenue after each Mac sale. A wireless service with Verizon makes perfect sense for the MBA first. Apple has used the MBA as its testbed platform for ideas.
The other thing Apple could show is where the MacFive are headed in the future with Core i-series CPUs with dedicated ATI GPUs.
Apple could use a 32 NAND Flash soldered to the board to run OS X and apps. It would provide a faster Mac for all Mac notebooks.
Apple could also use the displays to set apart Macs from alternative PCs. It seems obvious to me to make the displays of Macs the real reason to spend the extra money. We look at the displays every minute of every hour we're using our Macs. Improving the user experience is a big adjustment when it's a component that the user looks at every second while using a Mac.
Apple could also do something incredibly innovative... something we're not expecting... I would say rather than a touch screen why not an OLED large multitouch trackpad that displays the 13" full display in the trackpad. It could allow touch interaction with computer without touching the very display we want to look at for movies and etc.
Apple could also just change the design of Macs with the MBA first. For example, test a black anodized aluminum MBA. Or how about a ceramic or carbon fiber MBA like the new iPhone material might be?
Apple could also do something we are not capable of predicting??? It could be a new way to interact with the MBA via a motion sensor? Or even a video sensor? Could be a docking pad that charges the MBA instead of requiring a cable, just set MBA on the docking pad.
There are many things we could predict, but it will probably be something unpredictable as the glass buttonless trackpad was... it provided a much better interaction between user and computer but was very low cost. Same as material aluminum in Macs. Same as capability of mini Display Port driving a 30" ACD... could be using Intel wireless display technology?