these may not be failures, but they're certainly failure-ish. "less successful then the competition," as you describe below, is actually a pretty good definition for "failure.". And arguing that things are still a growing product is not a good defense- mobe me has been around a long time, for example, and has yet to gain any traction.
Maybe we should first define what a failure really IS before we discuss further whether any Apple products indeed are failures.
To me a failure is a product that generates less revenue than it cost to develop and produce. I don't think Apple has any products currently and recently that fall into that category. As most products we talked about are still sold, there can be no conclusive judgement made in that respect.
Another way to look at it is whether the thing is fulfilling customer expectations. That is difficult to judge, since people complain more than rave about products. I can see that people view MobileMe, iPod Shuffle and Apple TV in these categories, but also here I haven't seen any conclusive data about customer experience. Although the App Store Review process is apparently universally hated...
I don't agree that "less successful than competition is failure" is by default true. Just look at Apple themselves. Apple most likely sells less iWork suites than Office for Mac suites, but I would definitely not call iWork a failure. You can apply this logic to most if not many apple products.
edit: That's not fair, you added stuff while I was writing
At the point when Apple retires e.g. the Apple TV in the next year without a new update, I think we can safely say that it has been a failure. But I think there is still enough potential within the current Apple TV hardware to make it a great product with the potential to accelerate the sales with some marketing behind it.
p.s. I didn't say that no-one buys them (referring to iPod Shuffle). I haven't seen any people around with it, because they are just too damn small.. And I don't stand around in the Apple Store all day counting sold units. In addition, I didn't say of any product that it has crappy features.. Please quote me right.