Apple - Pro - Tip of the Week - Switching Apps Within Expos�:When I use Firefox I have multiple tabs in windows, but also multiple windows. The tab/window sorting problem is very annoying (only OmniWeb tried to fix that and I didn't like their vertical tabs, IE 7 is supposed to tackle it better) and this doesn't entirely fix that, but using Expose this way is indeed more efficient than using Cmd-Tab to find a desired window. F9 arranges all the windows, F10 leaves one in the background. I'm not sure which I prefer.
Once you have Expose invoked (you pressed either F9 or F10), you can toggle through your open applications and Finder windows by pressing the Tab key. Press the Tab key once and the next open application and its miniaturized windows come to the front. Press Tab again, it goes to the next open app. Want the previous app? Press Shift-Tab.
So now I'll be using Expose. Heavens, I might end up using Widgets -- if they put the darned things on the desktop where they belong.