When I posted the new System Preferences pane in Leopard earlier this week, I was a little disappointed to see that while the desktop had changed (here it is online, if you want to make it your own already-- thanks, Ryan D!), the screensaver had not. I figured this is because Apple wasn't bringing any new screensavers to the fold in Leopard, but that was premature-- here's a "Falling Photos" screensaver sent to us by Christian BS (thanks!). I would be very, very surprised if it didn't automatically pull photos from iPhoto for you, as apparently "you can display any photos this way." Also notice the clock-- we're told that it can be displayed on any screensaver you choose.
And he also sent us this video of the new Help system, which has a Spotlightesque bar in it that will actually let you search for clickable options. That's terrific-- no more browsing through a Help system to find a tutorial about how to increase the text size: in Leopard, you'll be able to type "text size" into the bar, and automatically get the commands right within that menu.