Regarding CarPlay wi-fi, I'm wondering how this might affect the Alpine iLX-007 (and maybe other third-party head units as well?). There have been persistent rumors that at some point this unit might develop wi-fi capacity, and maybe "at some point" means the release of iOS 8.3. This would only be possible if this unit contains Bluetooth circuitry waiting to be activated. Although there are plenty of reviews of it available on the Web, I haven't seen any published teardown that would establish whether this is or is not the case.
Alpine iLX-007 currently does not have any bluetooth feature. its competitor Pioneer Appradio 4 does have bluetooth. hopefully carplay use Bluetooth, instead of wifi, and require only firmware update, not hardware change.