I'm not sure why I upgraded today to Mac OS X 10.8 Mountain Lion. I have the most complicated Mac Pro setup around, and every time I upgrade to a new OS version when it comes out, I suffer. But I am an early adopter, so it's in my nature to do these sorts of things. It's how I learn, I suppose.
So far, I haven't noticed any striking new features in the new OS. I know there are many new features, but none of them have been really obvious, yet—at least, when using my computer in the normal way I use my computer. I am really looking forward to being able to share my screen via AirPlay, but I don't think my Mac Pro is supported, so I will likely continue using AirParrot to do the same thing. I'm not sure what else will be interesting. I'm not a Safari user, so all web-reading improvements are sort of lost of me. I signed in to Twitter, Vimeo and Flickr, but haven't seen any signs of integration, yet.
The Mail, Contacts & Calendars preference pane is a disaster. I opened it up and it doesn't match any of my Mail account settings—it pulls email addresses instead of actual usernames from mail accounts, and then complains that the passwords are wrong. It isn't obvious what it's doing.
Mail.app is now super slow. It is laggy—I have to wait seconds to do things—and I can't bring it to the foreground with a single click unless I click in the header area when it's in the background. I do have a 28GB mail archive, but Mail.app under Lion was fast, so the new one is definitely worse.
Most apps I've tried continue to work. I've had (only) the following problems, so far:
- Mail.app (performance) - YouSendIt Express (doesn't work) - Sonnet Presto Gigabit Server PCIe (doesn't work—apparently, I have the "old" version, which is 15 months old) - Calendar sync with Google (lots of conflicts, repeatedly) - Notification center (gave me the same notification every few minutes—I disabled it altogether)
The Sonnet Presto Gigabit Server PCIe card not working was a pain, especially because Sonnet tech support told me directly that it would work. This card is my direct iSCSI conduit to my ReadyNAS image archive (via LACP), and it took me awhile to figure out how to re-establish contact with the iSCSI target (which is configured for LACP, as well). I tried link bonding the Mac Pro's 2 ethernet ports, but it wouldn't connect to the ReadyNAS. I eventually solved this (temporarily) by configuring a bond in my switch and connecting the ReadyNAS directly to it (instead of directly to the Mac Pro). This worked, luckily, but going through the switch is definitely slower.
Again, I am not a normal computer user, so I don't know why I still try to do early upgrades. It never just works.
One last note: iCloud document integration will probably be great for folks who exclusively use 1 application to work with 1 document type (e.g., Pages for all word processing), but it will break down very quickly when used with file formats that are commonly used by multiple applications (e.g., save a picture with Photoshop, and then try to view it in Preview). It doesn't seem well thought out, but will probably be fine for the people out there who have no idea where they are saving their files...
If you want a great overview / review of 10.8, I highly recommend reading [the ArsTechnica review](http://arstechnica.com/apple/2012/07/os-x-10-8/), which is excellent.