(Lesser known) things I like about Leopard

1. Calculator.app sports a fully functional RPN mode. It's had RPN mode since Panther but it always seemed like a shoehorned afterthought. Switching to RPN never produced any change in the UI and RPN really demands a multi-line display. Now it has one. There's one quirk I've noticed: when you type a number and press enter, the number gets pushed up the stack (as it should) and then gets duplicated on the line below (not as it should). As soon as you begin to type a new number, the doubled entry disappears but it should never have appeared in the first place.
2. Calculator.app can now also display digit seperators.
3. The Airport menu (from the drop-down in the menu bar) now shows lock icons next to those networks which are protected. You can see at a glance if there are any available networks that are open.
4. Hitting command-backspace from any NSTextEdit field will delete from the cursor to the beginning of the line. This means TextEdit gets the "feature" I most miss when I'm away from TextMate.
5. iCal.app no longer changes the size of your window when you switch from (say) month view to week view.

ECMAScript 4 Overview (final draft)

The final draft of the Overview that describes what's going to be in Javascript 4 (E4) is online as a pdf.

Interestingly, this represents a point of departure from previous Javascript updates in that the group will provide a "reference implementation" in ML! And I though all that time I spent working in ML back in college would surely go to waste.

You can grab the standard SML release for Mac (as a DMG even) from here.