Mavericks is turning out to be a joke, and the deeper strategy here is long term profit.
Laptops recently ship with about 8GB of RAM, which is more than enough for the state of play. Apple know this, so they must protect their future profits in exactly the same way they do with iOS: develop software, apps and OSX's that simply consume more RAM. That way, your device slows down and you need to upgrade your hardware. It is a very simple trick. Once you have done that, the cycle then shifts to developing more programs or OSs that consume that RAM, that power hike, so you are effectively back where you started. Needing some kind of upgrade.
You may well argue that in Mavericks there is a bells and whistles way of "compressing RAM for smarter usage". Yeah right. Is that why my 8GB Macbook Pro starts beachballing when I use QUICKLOOK?!! (even when nothing else is running), and I am still showing as only 1GB free? Smart stuff.
iPhones are also subject to the same con. I remember when iPhone 4 came out. It was a genuine leap forward. So fast and powerful, everything ran so smooth on iOS 4 and 5. I remember thinking, why would we need anything more, apart from an even faster processor, or better camera?! Surely it cannot go backwards, right? Wrong. Enter the "lighter, faster, flatter and more efficient iOS 7" So much lighter, faster, and more efficient, that your iPhone 4 now grinds to a halt. Gone are the smooth, elegant transitions, the flowing scrolling. It's all glitchy now. Oh, and sorry, you can't go back. But hurry to the stores, iPhone 72 is here, it has more RAM and stuff (and probably still no bigger screen either). Needless to say, iOS 7 runs just fine on iPhone 5 and up. (That is, until a newer, energy saving, battery lengthening iOS comes out that will do everything it promises (as well as ensure that you should probably upgrade to enjoy the actual benefits you probably were enjoying before you upgraded).
And so it is with Mavericks. All these "improvements"... do I really need the Mac to compress (hog/consume) all this extra RAM just so that i can add 'tags' to my files. You could have given us that in Leopard or Tiger. Does it take 6GB of RAM to reply to a message in Notifications? And speaking of iMessage and Facetime, you better roll the dice to see if they actually work today or not. iMessages are always jumbled and totally out of order on the Mac. Why? Is it so hard to sort them by date and time like the iPhone 1 did with no problem at all?
Want more proof of my theory? The kicker is the new iPhoto. It 'upgrades' your library and conveniently tells you that you won't be able to view your photos on any previous version of iPhoto (which of course won't run on anything other than the OS you just upgraded to) - without it looking one iota different as a program. So, in case you sneeky people decide to find a way to go back to Lion or ML on the DL, you won't be able to take your photos with you. Or at least 95% of normal people (ie, non geeks who never visit these forums) will just stick with it and say, 'oh well I'm sure its an improvement overall'. It's an improvement to Apple's future profit, that's all.