The new Keyboard Shortcuts panel is very cool. It allows you to change
global keyboard shortcuts for the system as well as individual applications.
Caveat: Does not work on Classic applications or Classic
itself. For example, turning off Command-Option-D for hiding
the Dock in OS X works great, but when you switch to a Classic application
like QuarkXpress 4.x, the shortcut still calls the Dock.
Login Items has been renamed to Startup Items and is now found in
the Accounts panel, which makes more sense, because if you're an admin,
you can now customize multiple users' startup items at the same time.
Closing the System Preferences window quits it as well and behaves
like a control panel (Jaguar kept the app open).
Cons
No more Internet Preferences! In yet another Microsoftian move, Apple
has moved some of the global internet preferences to Apple's own applications,
and completely hidden other preferences. To set the global web browser,
you have to access it from within Safari; to set your favourite email
program as the default, you have to use Apple's Mail to do it. Other
protocols, such as the very important FTP, is nowhere to be found. In
order to change OS X's default behaviour of using the Finder for FTP
(and to set defaults for many other internet protocols), you can download
the free third-party utility, MoreInternet.
From all accounts on many web forums, you'd be well advised to stay
away from Panther's FileVault feature. This password-protects your home
folder, but many people have had problems with it, resulting in data
loss. Don't use it unless you absolutely have to, and even then, make
sure you do some research and testing first.