"This update extends RAW file compatibility for Aperture 2 and iPhoto 08 for the following cameras:

• Canon EOS 5D Mark II
• Canon PowerShot G10
• Pentax K2000/K-m
• Leaf AFi-II 6
• Leaf AFi-II 7
• Leaf Aptus-II 6
• Leaf Aptus-II 7
• Leica M8.2

It also addresses issues related to specific cameras and overall stability.
System Requirements: OS X 10.4.11 or OS X 10.5.3 or later"

" Multi-Touch Trackpad Update for Windows XP & Vista
This update improves the performance of the Apple Multi-Touch trackpad when running Microsoft Windows XP and Windows Vista on a Mac computer using Boot Camp.
For additional information about this update, please visit this website:
http://support.apple.com/kb/HT3336 ("About the Multi-Touch Trackpad Update for Windows XP and Vista 1.0")
For more information about bootcamp, please visit this website: http://www.apple.com/support/bootcamp/

Trackpad patch v 2.1.2.100 will be installed as a result of applying this update. "

I spotted some other Apple docs referring to this patch/update as a fix:

• Boot Camp: Difficulty using Multi-Touch trackpad in Windows
• Boot Camp: Difficulty using right click with Multi-Touch trackpad in Windows

FYI - I've also added a few updated OS X/10.5.6 related Apple troubleshooting docs (updated today) to the Other News/Articles links below.

" Cocktail 4.2.2 (Leopard Edition) has been released. This version addresses an issue in which clearing of user caches may cause Mobile Me synchronization to fail and adds Mac OS X 10.5.6 compatibility. Available now at http://www.maintain.se/cocktail/download.php"

There's also an update out for LCC (Leopard Cache Cleaner 4.0.19)

• Application Switcher Menu 2.2.8 (v2.2.8 restores dock menu support with OS X 10.5.6)
• Mac OS X 10.5.6: Mail unexpectedly quits (Apple)
• Cannot connect to remote Xserve using ipmitool after installing ARD Admin 3.2.2 (Apple)
• My iMac or Mac Pro stops responding while I'm browsing the iTunes Store (Apple - says fixed in 10.5.6)
• Apple Flavored Car Design From Britain (the iMo)
• Toshiba to unveil 512 GB solid state drive at CES
• Mac OS X on Netbooks: What Works, What Doesn't (wired)
• LittleSnapper 1.0.1
• Geneforge 5: Overthrow v1.0.1 Update For Macintosh
• Leopard Cache Cleaner 4.0.19
• OS X 10.5: Software Update stops responding during "Configuring installation" (Apple)
• JetPhoto Studio 4.0 (non-pro version is freeware)
• Pixelmator 1.3.2 (image editor)
• Monster Trucks Nitro 1.20 (Game demo)
• Battlestations: Midway 1.0.3 (updater, v1.0 demo available)
• StuntMANIA!pro 3.0.2 (game demo)
• Dodge That Anvil! 1.0.6 (game demo)
• Apple May Not Need Macworld, But Many Apple Partners May (Businessweek)