I would buy the iPad Air if I could afford it. Seems like they have made a lot of improvements in the features of the product. Also with its light weight, it would easier to hold and easier to carry around. I think they have other improvements to go with it, and I would buy it if I was in the market for one.
Over the past few years there have been iPads, I've had them. It's a great little product from Apple that does everything I need it to do, and it's a lot easier to take it with me than lugging a full computer or netbook around. The operating system has gotten better and better with each release. I would most certainly buy an iPad Air when I feel it's time to upgrade my hardware.