Filed under: Software UpdateApple released the Magic Trackpad this morning, but the OS update to make it work with your Mac is out now, available via Software Update on your Mac (drop down the Apple menu on the left if you've never done this before). Here's the link for a download of the update.
This update also enables three-finger drag gesture and inertial scrolling for older Mac portables listed on this support page for the update.
Oh, and there's a new Preference pane! From Apple's page:
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