This has been one of the things that I've liked about Apple.. they don't continually promise you the moon, then eventually release something that only gets to about 10,000 ft or so instead. At least not in the last decade plus. Not so sure about the pre OSX days as I was never much of an Apple user before OSX 10.4 or so and my first other Apple product was a 3G ipod.
What you're saying, that usually the "missing" features are only things that were rumored is exactly true. Look at things like the AppleTV. Most every complaint are things like, "It doesn't support codec $foo," or "It can't run $bar." Things that Apple never said the device would do. For Apple stuff, if you like the features listed, then you'll be happy. If it doesn't have features you'd like, don't buy it. Simple. Me? I've been happy with my Apple TVs, my ipad and my iphone. I'm a linux admin for work (and have my own linux boxes too) but the feature set of the Apple products is good enough for me and don't require me to have to essentially admin my devices, or root them or whatever. Would I like some of them to have some other features? Sure... but I knew what I was buying and have gotten what I was promised (no having to send my iPad back for a few weeks to get feature that was originally promised out of the box, for instance). Can't really complain about that.
Personally, I much prefer the Apple way of telling you exactly what their products already do, or will do in a very short amount of time (already in production as someone said) vs the crazy promises then half-assed actual delivery, often much later then promised as well. As time has gone on, they'd often added new features in new iOS releases too. Bonus.