"it's Apple's easy iTunes experience that has consumers buying iHardware in droves"
I don't think this is true at all. It was definitely a factor when talking about the iPod but so was a nice UI on the device, smart industrial design and good marketing. Along with pretty decent pricing.
When it comes to iMacs or Macbooks I really don't think iTunes is a factor at all, you can download it for free for their (cheaper) PC competitors after all. If it is a part of iPhone buying decisions I'd say it's a relatively small part.
I'm far from a fanboi but I do occasionally buy their kit.
I switched to Android when I judged it had matured sufficiently and wouldn't change back but I used iPhones for a couple of years. Not because of iTunes or anything like that but because it was (in my opinion) the first smartphone to provide a truly usable web browser and nice touchscreen-only UI.
I use a Windows desktop (self-built) and my previous notebook was running Windows (a Dell). I bought a Macbook Air a few months ago because I wanted something light, fast and robust with a very good screen that looked nice for bringing to meetings with customers and wasn't a pain in the arse to carry around a lot. An ultrabook, in short. I bought the Macbook Air because it was the nicest one around by far and was the same price or cheaper than the competition at the time. MacOS wasn't a factor in my decision (although I quite like it now) and iTunes certainly wasn't, VLC was one of the first things I put on it.
Lots and lots of people buy Apple kit because they like the hardware or the UI. I know far more people with Apple kit who hate iTunes than like it and I don't think I know anyone who bought an Apple computer or phone BECAUSE of iTunes.