Apple has recently updated a few knowledgebase articles that discuss some errors you may see in iTunes, problems with using startup hotkeys with wireless keyboards, and a few how-to and information articles regarding diagnostic data collection, installing RAM, and advanced uses of DisplayPort connections on 27" iMacs.
This article outlines a problem in iTunes where the program will display this error message when attempting to create a backup of an iPhone or iPod Touch. The error may not be exactly the same as this, but usually will happen if the backup file being updated is somehow corrupt. To fix the problem you will need to delete and recreate the backup file.
Some early Intel Macs came with 32-bit processors, so even if you are running an Intel Mac you may not be able to run programs and Snow Leopard in 64-bit mode. This article covers how to easily find if your Mac is only capable of 32-bit addressing.
Apple has had error reporting features in OS X for years, but in the latest 10.6.3 update Apple introduced options to report anonymous usage of third-party devices and applications. This is an option that will be presented to you the first time an error occurs in 10.6.3, but this article covers how to manually enable or disable it. You might also search for "sending diagnostic and usage reports" in the Help menu (with the Finder activated) to read more about error reporting features.
The displayport connection on the new iMacs allows for the internal display to be used by another computer. This article discusses how to set this up, and has helpful pointers to keep in mind when running the computer in this mode.
This article outlines how to install RAM in the latest iMac models. There are some precautionary steps to take, so be sure to give the article a read if you are going to manually upgrade your computer's RAM.
Wireless keyboard are not recognized immediately when the computer is booted, which may prevent some startup key combinations from functioning properly unless they are pressed at a specific time. This article covers the affected combinations and how to properly use them.