Well two days ago I upgraded from an iPad 3 to an iPad Air, and to say it is better and faster is an understatement. To start, I was amazed at the thinness of the Air. I know that factor was hyped but to see and feel it makes you a believer. That size change and other internals also reduces the weight which also lives up to the marketing.
Well now to the particulars. The setup went off with only a small hitch during the activation process. I got an error message and that error message was very unusual so I called Apple support. Even to them the error message was weird. The end result was turn it off and start again,which I did and all things went well. Depending on the number of apps, data, and pictures you have, expect about an hour to bring your new iPad total ready to use. Oh by the way, the Apple support staff was great, cheerful and very helpful.
As you most likely know Apple reduced the LED bar's to one and as far as I can tell, it made no difference in brightness or clarity. The readability is equal to or slightly better than my old iPad.
Aside for size and weight, the biggest changes are the processor, touch screen, and wifi components. First the processor. The A7 chip speeds things right along. Compared to the iPad 3, it is measurably faster and I expect this will continue to improve as apps progress to 64 bit.
To these old hands, the touch screen is a bit more sensitive. I am a tapper, as my iPads 1,2, and 3 required a firm hand. This new touch screen does not seem to need that same approach. In fact to those of us with a bit of unsteadiness in their hands, the increased sensitivity and speed can take you to places you didn't intend to go.
The two antennas combined with the multiple in and multiple out (MIMO), and dual frequency radio really sped up my download speeds as compared to my old iPad. Not that I am in any hurry, however I seem to get a bit more out of my internet service than I did before. I say this with one caveat, I use a dual frequency router as well.
The back camera produces pictures that aren't bad but still not great, however they can be vastly improved with iPhoto. The face time camera is improved however the one complaint I do have about its improvement, is that it shows all the bumps, scratches, wrinkles, and scars that come with age.
With the new iOS devices you get Pages, Numbers, and Keynote (Apple's version of Office) as well as iPhoto, Garage Band, and iMovie for free. I have used all of these apps except Garage Band and they more than meet my needs.
Was the upgrade worth it? Absolutely. With these changes, I have moved one step further away from my PC.