So I got my copy of Panther a day early, but took my time backing everything up and installing it due to the general crappitude of a cold that preceded it. Nonetheless, there are a couple of cool things I’ve picked up from the various sites.

One is that any Cocoa (that is the name of the native programming API for Mac OS X apps) text field has auto-completion enabled. This means if you can spell the first few letters of a word correctly, hitting F5 will generate a drop-down list of possible completions. If you type a long word early in a field, such as “programming,” the drop-down starts with that word the second time you start to type it and hit F5.

Generally, my ancient PowerBook (vintage 1999) is much snappier, and some UI elements have been sped up by default, such as the sheets that have mostly replaced modal dialog boxes (and good riddance). The UI is overall cleaner, and tabs have been redone in a cool way. Nice thing I discovered that I think is new: there’s now a menu control for the VPN, so I don’t have to keep the Internet Connect app in my doc or even run it while connected. The Finder (equivalent to Windows Explorer) is much, much more sprightly, and opening files seems quicker.

By far the most improved app is Mail, which gets threaded views that are automatically calculated by subject line, as far as I can tell. This will improve my archiving of e-mails at work. It also plays sounds when you do various things, such as send mail. I’m not sure how I feel about those yet, but they don’t immediately strike me as super-annoying. Bad thing: it now checks the certifications of mail servers that you securely authenticate to get mail from. So this means our do-it-yourself cert at work pops up a sheet every time I launch the app. This would be fine if there were an option to permanently accept a given certificate.

As many others have said, Exposé is a nice feature, and the standard trick of holding down the shift key while a Quartz animation plays to slow it down makes it nice and dramatic. Switching applications now pops up a translucent set of large icons with application names, á la Windows.

Other bad things: I had one system freeze which even stopped my PowerBook from responding to ssh. From reading other people’s reports, this happens when there is a fair amount of data I/O, though whether disk or network I/O is unclear. It’s only happened the once, and that machine has had operating system after operating system installed on it since at least OS 8.6 or so, without clean reinstalls at any point–and that includes OS X since Developer Preview 3.

This is definitely a the best OS X yet, though I think we’re still at least two releases away from the best-in-all-categories OS that I think Apple is capable of. It will take me some time at work to tell if it is worth the $130 that Apple charges, upgrade or no upgrade.

Still, beats paying Redmond for ugly crapware.