I upgraded to OS 10.8 the other day.
Nope, not my main system. Not the iMac. Just the MacBook Air.
I realize that it’s the Golden Master, and there isn’t really much difference between it and the official version. But the little bit of risk is still a risk, and I’m not about to subject my main system to that. Best to wait for July 25 when it finally, officially comes out. Just a couple of weeks. (By the way, in case you don’t know, I’m a registered developer, although it’s more of a hobby than anything else.)
That said, let’s look at OS 10.8, or Mountain Lion, as it’s better known.
I copied the image file from my iMac via a Shared Folder on the Air, and it took twenty minutes or so. Then I installed it, which was a straightforward process. About another twenty minutes, and it was finished. (I realized it was kinda fast, but that was largely because of the speed of my Air’s SSD drive than anything else.)

Nothing much different on the face of it. Some new icons popped up on my dock: the return of Launchpad, plus buttons for Notifications and Notes. Knowing I wasn’t really going to use these icons much, I quickly deleted them. After installing the OS, there were a few further updates to be installed, but not much – the biggest was the Samantha voice that I had installed on my OS 10.7 system, which was a 400+ MB download, and some Java updates. After that, it was back to normal. Or at least as much as normal as was possible.
There was a new icon on the menu bar at the far left – a Notifications indicator, which at the moment had no new Notifications. This is an iOS-sourced app, which further gives Apple’s unifying of the Mac OS and the iOS more credence. (I noticed, while swiping between my different desktops, an app I had installed to maintain maximum free memory, iFreeMem, popped up everytime I switched desktops, just for a second, before disappearing into the background. Every single time. Must be some glitch in the matrix that had yet to be sorted out.)
Other than that, Mountain Lion looked like Lion, its predecessor. It felt a little bit snappier, but that could just be my imagination.

A few changes showed up in System Preferences. There were a couple of new icons there: Notifications, which managed the Notifications Center, and Dictation & Speech, which handled dictation and speech preferences, an new iOS-derived feature which allowed you to dictate text entry. Some of the visuals had changed for some of the Preferences, mostly cosmetic, like Display and Print & Scan, but some had some more fundamental changes, like the Privacy tab on Security & Privacy, and the Slideshow and Screen Saver portions, which provided some new stuff. There were also some great new Mountain Lion wallpaper thrown into the mix.
Time Machine can now simultaneously save to different places, ensuring better and more reliable backups.

When I first clicked on Software Update on the big Apple on the top left, I was a bit surprised . Clicking on it now brings up the App Store, indicating a change in Apple‘s preference for updates to pass through the App Store now instead of a more direct download.
Safari Ver. 6 has a lot of visible major changes and tweaks. Notable is a new feature which allows you to scroll between active tabs by clicking on a button at the far right of the Tabs row, and further clicking on a tab brings that tab to prominence.

There’s also a new button that allows you to share what you’re looking at in Mail, Messages or Twitter by providing a direct way to post from the Safari menu bar. (In fact, Share is ubiquitous; it’s practically in every part of the system now.)

There’s also an iCloud button in Safari’s menu bar that shows you all the open tabs on your other devices, and there’s also a Reader button on the far right of the indicator bar. Safari has also dispensed with the Search portion, and now you just have to type in your search in the main indicator bar (which does it all, apparently) and you’re brought your preferred search screen.. (There’s a new plug-in blocker that irritates me, though. Some of my regular sites are suddenly rendered ineffective because of this, and I have to figure out how to circumvent it.)
There’s a ton more of changes in the OS, big and small, like tighter integration with iCloud, and being able to sync accounts across multiple devices, but this has just been a preliminary look at the golden master version of Mountain Lion, which becomes officially available for download on July 25 for US$19.95 worldwide. We think we’ll wait for it before we give you guys a more comprehensive review.