This may be an unknown right now, but I have to wonder what apples new software update in the fall will mean for current owners of mavericks systems. Yeah, free update and all of that, but will it require more from the operating system than what mavericks use now? Will 4gb , 128gb for the low end models be enough? I haven't seen any reference to this at all. From what I gather this is a tick and not a tock so we're talking about a software issue instead of hardware, correct? Also when the hardware changes with the tock will that be a problem? I would hate to buy now and want the upgrade in the fall for the use of a smart watch, upgrade and have my air whine like a jet engine just to try and keep up. However many of the new features this software may provide may not be something I'd use anyway.