Nothing Apple has compares to Windowshade. I will not go Lion until absolutely forced to. From what I've read it I'm not missing much, at least in my personal workspace. Love Apple, but their sadly missing the point here.
Having multiple desktops is time consuming and clumsy; and does nothing to mitigate the problem of several open "being used" windows.
It's not unusual for me to have several windows in play at once: ftp, an html editor, several html pages, photoshop, et.al. on the desktop at the same time - without WS that would be 8 or more "icons" in the doc, none of them easily identifiable, and time consuming to view/open/ etc.
WS makes it much faster to have a small window bar with visible title in a given position on my monitor, where I left it a few minutes ago.
Nothing comes close to Windowshade. It's so obvious and useful I don't understand why Apple abandoned it.
Maybe Steve didn't like it.