If you didn't live stream it, you can see the video here.

My initial impressions include:

iOS 12

• speed improvements via changes acceleration profiles
• a new image format/standard for screen capture including video offering file size reductions of up to a n order of magnitude
• ARKit (augmented reality available to developers
• Stunning 3D
• Major developers such as Adobe and Lego already have products in beta using ARKit technologies
• new builtin apps (include potentially very useful new functionalities)
• major enhancements in iTunes and Photos including lots of AI
• enhanced interoperability between iOS devices and MacOS devices (MacOS app can open the iPhone camera and grab the image seamlessly),
• security enhancements,
• Siri enhancements including opening Siri up to third party developers for use
• new Animoji,
• Memoji (your custom animoji
• new customization features,
• new App Store,
• Facetime with up to 32 different people in the same conversation (IMHO this is HUGE)
• Third party navigation apps available in CarPlay (at long last)
• Measure: an app to accurately measure objects in one, two, or three dimensions (I can already envision hundreds of uses for this app at home, in the workshop, just about everywhere)

MOJAVE (MacOS 10.14)

• offers universal dark mode (This was a huge hit with the developers who spend their lives staring at computer screens)
• dynamic desktop that changes the UI color to match the outside lighting
• desktop stacks (at long last a quick and automatic way to organize all those icons on the desktop)
• gallery view in Finder (could be very useful for certain kinds of files
• Markup in Quicklook with several builtin and very powerful actions as well as user created actions, workflows, etc.
• changes in the UIKit that make it easier for iOS apps to be ported to MacOS (look for a slew of iOS apps to show up on MacOS)
• News & Home from iOS now available on Mojave thanks to the changes in the UIKit. (about time too)
• new App Store

In general, while I didn't see any earth shattering new features, the Quicklook enhancements and interoperability between MacOS and iOS features will probably have a major positive impact on my workflow. Hopefully the public beta releases will be out in a few weeks so I can begin to sort it all out.

It was only a throwaway comment in the conclusions, but also:

MOJAVE (MacOS 10.14)

• APFS for Fusion drives and Hard Disk drives.

macOS Mojave will drop support for some older Macs released before 2012

"Major developers such as Adobe and Lego…". Now that's an odd couple that in the past one might not imagine ever appearing in the same sentence.

"Markup in Quicklook…". Also the ability to annotate screen shots was mentioned.

Thanks I missed that one. It was expected and IMHO overdue. I can't wait to see what if any other features of APFS have been turned on or at least made more accessible in the GUI. Features like Time Machine on APFS, APFS on RAID arrays, snapshots, Character by character or word by word versioning. I wouldn't be surprised to see some of these features added one or two at a time during the beta release process.
Agreed, but as they are in entirely different app categories (Photography and Games) it accentuates the breadth and depth of the App Store offerings.

Speaking of games, the ARKit looks like a real game changer (double, maybe even triple, entendre intended). I want to try out some of those games demonstrated during presentation.
Not just annotate screen shots but take screenshots and edit them. It transforms Quicklook into a powerful and essential tool for users and developers alike. It is most definitely one of the features I will be looking forward to trying out, and may replace some third party utilities I now depend on.

Apparently, my Mac Pro 5,1 (late 2010) is on the cusp. Depends on my graphic processor, and I have the cheaper one. Don't know if you can buy a new card that will keep in up-to-date, but I suppose I'll run it 'til it breaks, then buy an iMac.

Too bad. This has been/is a terrific computer.

At the end this "innocuous" comment was made: "macOS Mojave will abandon a number of Mac models supported by macOS 10.13 High Sierra."

What does that mean? It's not a reference to abandoning 32-bit support; I thought that was with the OS after Mojave.

It means my iMac Mid 2011 will never see it. 😔

Wasn't support for 32 bit apps originally supposed to be phased out in Mojave?

No complaints, nor am I expecting any miracles, but the extra year will be appreciated.

My interpretation was/is there are a numbrer of Mac computers that will run MacOS 10.13 High Sierra that will not support Mojave (a.k.a. MacOS 10.14). OSX Daily and others have published lists of Macs that will support Mojave. The deciding factor in a Mac's ability to run Mojave is whether or not its GRAPHICS processor can handle Metal®. Any Mac that will run High Sierra has a 64 bit processor but not all of them have Metal capable graphics processors. ARKit and all of Mojave's amazing augmented reality and 3D graphics are based on Metal.

Like many, I have interpreted Apple's warnings about 32 bit apps to mean they would not be supported by Mojave, but I have not seen anything absolute on that. I guess I will find out for certain when I install MacOS 10.14 Public Beta 1.