If you're using an Apple Wireless Keyboard with OS X 10.5.8 or later, you'll want to install the Wireless Keyboard Update 2.0 from Apple. Released on Monday, the firmware update allows you, as Apple puts it in the release notes, to "take advantage of your 2009 aluminum Apple Wireless Keyboard's special features." The release notes are less detailed about what those features might be, but a pretty good guess might be the keyboard's function keys, which offer one-touch access to OS X capabilities including Exposé and Dashboard.
What about OS X 10.6 users? Worry not--the Wireless Keyboard Update 2.0 is included with the Mac OS X 10.6.2 update that also came out on Monday. You can get the details about what else is new in 10.6.2 elsewhere on Macworld.com.
Wireless Keyboard Update 2.0 clocks in at 10.95MB and is available now.
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