Well, there’s little actual information to add to Gruber‘s and TidBITS usual comprehensive write-up, but maybe I can explain some parts in more detail, or provide an opinion on how this will impact developers in the future.

Regarding SDK details as such, most of it is under NDA, which I signed yesterday; but some details have been published already. It’s common knowledge that it includes Xcode 3.1, which will very soon be available as an independent (and free) download, and of course included on installation DVDs with any Mac as soon as it gets out of beta. It also includes Interface Builder 3.1 but not the special objects to directly build iPhone windows; this will no doubt follow in the next release.

I was looking forward to getting my hands on the iPhone UI – to date, I haven’t seen one in the flesh (same for the iPod Touch). But fortunately the simulator includes Safari, so at least I can check how this site looks; some pages come in too wide, and I’ll tweak them as soon as I find time. Still, the UI for the few included apps looks great and it’s useful to get a feel for all the animations. Speaking of the simulator, it’s not a hardware-level simulator; it seems to run x86 code, no doubt an easy way to make it even harder for hackers to glean information about the actual iPhone OS implementation.

I suppose this would also explain why the current SDK is Intel-only; the PowerPC version might not have made it in time, or may be too slow, or whatever. Still, it’s a bad precedent. Intel Macs seem to be about 50% of the installed base by now, a year before I thought that would happen, but it’s still too soon for people to stop doing Universal applications. For what it’s worth, I had to install everything on the only Intel Mac I have – a Core Solo mini with 512MB RAM – but it seems to run quite well despite the cramped hardware.

This “iPhone OS” name now seems to be the new “OS X” and it’s… clumsy. Not a good way to indicate a new platform that already includes the Touch and before the end of this year (or so I think) will get new members. Indeed, there are hints that both “mobile” and “touch” were at one time or another the platform name du jour, and hopefully this will prove to be just a beta name.

Certainly nobody in the Mac developer community was surprised that the SDK is based on Xcode, Cocoa and Objective-C; doing otherwise would mean a complete rewrite of the current 1.1.x firmware, and Apple hasn’t enough manpower to pull such a thing off. Besides, it’s certainly a good way to get Macs into the hands of new developers. Still, no doubt some people are miffed or surprised that the SDK doesn’t run in Visual Studio, or that there’s no Java or .NET support; I can imagine them complaining to Microsoft about this (hey, Microsoft owns a good chunk of Apple, or so they probably believe).

Next: the business part. That’s where it gets interesting.