where is the option in the latest amaroK to make the playlist jump to the currently playing song?

I remember seeing it in older versions, but I can no longer find it. Does it still exist?

We've removed the action from the menu, but you can still add it to the toolbar by doing "Configure Toolbars", and adding "Go To Current Track". Then the keyboard shortcut will also work again.

Is there a way to make amaroK automatically jump to the playing song without a key needing to be hit?

Yes, it does that anyway, by default. That's why we removed the action from the menu in the first place.