[search was down, sorry if this has just been asked]
There's a contextual menu item in iTunes, called "Copy to play order", which appears when ctrl-clicking a song that's in a playlist. (Not Library.)
Bad Apple, bad - it isn't available through the application menus.
So what does it do?
EDIT: lol, I was so pissed off at not figuring it out myself I kinda 'forgot' about this 'goggle' thing they have at teh intarweb.
Here's the answer.
J