I've been thinking about something I'd like to see with stacks and the dock and, like you, have been worried about the notion that I "want what Windows has." But since you brought it up...

The thing that always clutters up my dock is the crazy collection of minimized Safari browser windows (each of which contains any number of tabs). My dock just fills up with minimized windows. It also happens with Preview and minimized PDFs. In fact, it happens all the time, even when I separate applications into Spaces (because the dock remembers everything that's minimized, no matter which Space the application resides in).

With OS X (and lately Safari) never crashing, I end up browsing and working in so many directions that I can easily have a dozen windows from Safari, Preview, or Word lined up in the dock. After a while, the dock fills up and becomes cumbersome to access and (to me) rather unsightly.

What Windows does when you have too many application windows open at once is to create, you guessed it, a dynamic stack of buttons. Suppose you have six IE windows open. Instead of having six buttons down on the start bar, you have one button. Click on it and you get a list of all the open IE windows from which you can pick the one that you want to un-minimize.

I want the Leopard dock to do that. If I have more than one Safari (or Preview, or Word, etc.) window minimized to the dock, I want Leopard to dynamically create a stack of Safari windows that I can click on to see thumbnails from which I can pick one window to view.