Another senseless idiot Apple "Genius." All one has to do is consider the differences between the MBA and iPad to understand they're marketed to two completely different groups of people. Sure, some of the people who bought "dumped" original MBAs for $999 will probably buy an iPad next time, but that doesn't mean the iPad is a replacement for the MBA.
The MBA's form factor is the future of the MBPs and MBs. We have already seen it as the MBA was first to sport the unibody design, large trackpad, non-removable battery, black keyboard, and other design elements. I fully expect the MB and MBP to eventually drop the optical drive just as the MBA and to also focus on wireless tech rather than ports. The future MBs and MBPs will be thin and lightweight like the MBA but will do the full workload required of the MB and MBP buyers. Does it make any sense at all for Apple to EOL the MBA unless it's changing the MB and MBP into MBAs of sorts? The Mac computer, especially not the MBA, is threatened by the iPad at all at this time. In the long run, the iPad will change everything... but it's going to be many years before the iPad seriously challenges the Mac for workload tasks... for observation and entertainment, the iPad will succeed sooner rather than later.
The MBA is a luxury computer intended to be sold primarily to the business user/traveller/tech enthusiast willing to pay for the premium experience sold for ultraportability yet solid MB like computing that does real workload tasks. It's a premium device; technology always costs more when it provides a superior experience that requires less space or weight when on the go. Sure, the MBA user can view videos, read text, surf the web or check email from their MBA, but they also can do real work! Try typing a report on an iPad, and that's just the start of it... as the MBA has real computing capabilities.
The iPad is a consumer device being sold as an entertainment device that doesn't do any real computing. The iPad allows someone to view anything from text to video, observation only. We will call it "input." The MBA allows input and output of information. There is the main difference and it's gigantic. The MBA allows people to do and see while the iPad just allows people to see. That is the primary difference that is obvious and tells us just how different these two products are right now. Information and ideas flow out and in on the Mac while info only flows in on the iPad.
I see the MB being challenged more by the iPad than the MBA. Think about who buys the MB, consumers. Many of these people don't do anything other than watch videos, read email, and surf the web. These people will definitely consider the iPad as an alternative. Anyone that mainly observes on the MB will see the iPad as a better experience. Anyone that has to work on a MB, will see the MB as the only way to get real work accomplished. The keyboard is a gigantic difference and the differences get greater from there when considering computing performance and capabilities of the Mac over the iPad.
Honestly wdropo, you should know better than this. I am disappointed that you didn't challenge this "Genius" and come up a strong argument against what this "Genius" told you. You're far more likely to learn something about Apple's business model in the MBA section at MacRumors.com than you are from a "Genius."
I don't expect the MBA to go anywhere... and Apple didn't create the iPad to sell less MBAs to the luxury computer market. If anything, Apple created the iPad to further allow the MBA to succeed as a premium device. When there was no iPad, the MBA had to be temporarily repositioned (last June) to help take advantage of those who wanted an ultraportable device since Apple didn't have a netbook device. It came as an unexpected and unintentional repercussion for Apple when its first MBA failed miserably and it had to dump them for $999 just to get them out of inventory. Also, the netbook had taken off and Apple didn't have a device that was positioned at a lower price than the MB that offered just the "observation"/input not the ability to work on device like a MB (or "output"). Apple countered by reducing the price of the MBA in June 2009 to take advantage of those willing to pay a lot more for a device they could observe on and was ultraportable. These people don't fully utilize the MBA for its power, and some of them will be better off with the iPad... so it allows the MBA to go back into its traditional role as an ultraportable luxury item that allows MB like computing experience for the business pro willing to pay more money for a premium device. Apple will focus on the MBA being a luxury item that does input and output as a premium device for those on the go.
I expect MBA prices to rise slightly with its next update. Pricing could remain the same, but we actually want them to raise the prices which will mean Apple is repositioning the MBA back where it was intended to be - the premium luxury computing experience for those willing to pay more for a super portable computer that allows them to do observation like watching a movie, reading the web, checking email and also allows them to do daily workload from apps that they need to complete their work.
My iPad will not replace the work I do on my MBA. My iPad will be for input/observation of information (primarily entertainment), while my MBA will be both input and output of information (primarily work). I am just testing the iPad too. I don't know if I will like carrying two devices when I am traveling. The iPad might be better for a movie on a plane, while the MBA will be better for typing a proposal or writing a business/marketing plan. And let's not forget we will all need the MBA when doing serious web browsing as the iPad has no solution to provide Flash content whether it's just a navigational bar or a hulu.com movie for free vs. paying Apple for the same entertainment. There is some overlap, but the real person wanting to do work on their Apple product will be buying a MB/MBP/MBA and not an iPad.
-ADD- | -EDIT-
Observe = Input = from computer to brain
Action via KB/Mouse = Output = from brain to computer
I definitely could have clarified that better... sorry. It almost seems backwards, but it seemed backwards no matter which way I typed it. Rather than going back and fixing, I figured clarification here was best.