* The SSD is replaceable, but based on PCIe, not SATA. Replacements are available from Transcend ("Jetdrive") and others. "Normal drives" don't fit.
* RAM is soldered to the board
You actually can upgrade the SSDs http://eshop.macsales.com/shop/SSD/OWC/Air-Retina/Apple-MacB...
Isn't the SSD soldered to the board now? Do the new models even have SATA connectors? Do normal drives even fit in that slim enclosure? I'm not even certain if the RAM is upgradeable anymore, are you sure about this?