Which is fair enough, but if you look at the amount of effort they are putting in to bring Swift's documentation / tooling up to speed, it seems pretty obvious that Apple themselves have high ambitions for the language.

Also, it's going to be hard to tell how much Swift code is being shipped by Apple - the interfacing with existing Obj-C code is sufficiently clean that it's relatively simple to have parts of a product implemented in Obj-C and other parts done in Swift, and we, sitting on the outside, may never know.

I recently learned that core data wasn't used internally at apple. That freaked me out, because it made me feel that choosing that technology for a serious project was a mistake, despite the numerous documentation and support apple provides for it.

I don't understand why people use Core Data. The sweet spot for Core Data is really tiny, yet everyone seems to be using it (and regretting it).

Really? Not that I'm doubting you. Could you please provide me a link so that i can educate myself?

Unfortunately it's not a written statement ( you can imagine that nobody working at apple would publicly say a thing like that). And it's not a direct source either, so you can very well take that with a grain of salt.

Actually, I am still hoping that someone will contradict me by providing concrete example of apple software using core data though, because as i stated, i invested a lot in that technology for an important project.

Well, the Notes app on Mavericks uses Core Data. I know it's a trivial example but it's the first one I found.

(~/Library/Containers/com.apple.Notes/Data/Notes/NotesV2.storedata is a Core Data SQLite store.)

I can tell you that many projects have used CoreData, and abandoned it in short order.

Largely because it is a complex beast that many don't bother to become familiar with before they use it. Perhaps that is damning enough.

Lots of SQLite and PLISTS prevail, perhaps indicating the domain of data that needs to be stored for your average application.

I got a request to share my project (15k LOC) with the compiler team because they had no larger projects to test on. This was less than a month ago. Draw your own conclusions on how much Swift has been used internally at Apple. Oh, and compile times for any change in that project was 50-60 seconds. That's a minute for changing a single character in one of the Swift files.

Since they don't seem to be scrambling to fix that problem, I can only assume that there's no urgency internally at Apple to fix it.

WWDC app.

They said they made a version of it in Swift. The actual version deployed on the App Store was written in Objective-C.

Are you sure? That's not what I heard, but I could be wrong.

I tried to hunt down the statement but without success. If I didn't imagine it, then I'm fairly sure it was in the Apple dev forums. However, I did find a posting where someone said they hadn't found the Swift runtime libs bundled with the WWDC app.

So, either the WWDC app had the Swift runtime statically compiled into the app, or it was written in ObjC. Checking the size of binary of the app should give a hint - the runtime libs you need to bundle are huge.