Just because they say they will support HomeKit doesn't mean they're dropping everything they're doing to support it right now.
As for shipping goes, they are shipping regularly. I've already heard of people in the 1,900 - 2,000 range receiving their units since shipments resumed at the end of May.
As far as HomeKit goes, it's pretty much almost fully "baked" in to iOS 8. There is a video from a developer session talk that can be viewed on Apple's WWDC site.
I'll also copy and paste a summary I posted on Reddit:
"From what I've read and understand so far, HomeKit is essentially a hub without the hardware.
The idea is that it acts as a central database in iOS for all your home automation stuff to "register" with. The registration would have to be handled by an iOS app. Once registered, HomeKit lets the app developer to associate things together to your liking.
The structure is:
which contain Rooms
which contain Items
Items can have Services available (thermostat, lock, switch), which provide actions (set temperature, lock/unlock, on/off).
These items can then be grouped into Scenes, for convenience.
All of these items are then exposed to Siri, so you can optionally use voice control to interact with the whole "home", a room, an item, or a scene.
The key here is that they are not creating a whole new standard and protocol for things to connect with. HomeKit doesn't care how your devices are connected, or even if they're behind a hub. All that HomeKit is concerned with is giving HA iOS developers a spot to pool together control information. So if your iPhone can connect to it, or control it, then the app you use today can have HomeKit added to it.
For device manufacturers, they can contact Apple to have HomeKit support built in to their apps from the start, and communicate with what's built in to the iPhone/iPad (Bluetooth LE, Wi-Fi), without having to go through a hub. This still isn't required to have your device or app work with HomeKit, it just gives manufacturers a way to "certify" so they can guarantee compatibility."