There is more fallout from the current Leopard update to version 10.5.6. Many users are flocking to the Apple support forums to share their tales of woe about Time Machine failures after the update. (Ironically, Time Machine was on the list of items that received bug fixes).

Upgraders are seeing Time Machine stall, fail to identify the target hard drive, lock up while Time Machine is 'preparing' to backup, and other assorted glitches. There is no guarantee that these issues were caused by the update to 10.5.6, but users are seeing a lot of problems in parallel to the software changes.

MacFixit has quite a bit of guidance on the Time Machine issues. One of the most interesting observations is the long pause while 'preparing' to backup. It seems TM needs to do a deep traversal of the data because it sees a lot of file changes to copy, as would be expected with a major software update. The advice is to wait it out and and eventually TM is likely to get going. I had the same issue and eventually stopped the process, erased my TM drive and started again. That was after more than 2 hours of 'preparing'. It looks like I might have been better off to wait.

I had hoped 10.5.6 would fix the occasional TM error I get telling me that the backup failed, but then when I try again, everything is fine. I spent a good hour on the phone with Apple support on this problem some months ago, but didn't get anywhere. Many others have seen this rather arcane message and reported it. Hopefully it will be fixed in the next OS update.

It's good to keep in mind that most people updated without any dire consequences, but there are enough people grumbling that it merits a closer look by Apple.

• AppleScript can now read and write plist files (whilst a little thing, and a niche feature at best, this is promising if you're wanting to backup items such as serial numbers for applications from the application plist files, and do it in AppleScript)
• .Mac syncing of more system items (Dock items, Dahsboard widgets, Mail notes and, it appears, even the entire System Preferences)
• TextEdit now support Open Document and Word 2007 files.
  
• Open panels now have a Media Browser tab, allowing you to open items directly from the relevant location.
  
• Library Randomization - identical to Windows Vista's Address Space Layout Randomization, meaning that people looking to exploit Mac OS X can't rely on system code being at a specific memory address (i.e. it's harder to persuade an OS X system process to execute malicious code). Whilst Apple has always touted the more robust security of Mac vs Windows, it's good to see they're not sitting on their laurels and becoming complacent with OS X. Also of note is the digital signature technology in all the Leopard applications (and third-party developers can sign applications too). I've always believed this to be a technology that would be used in any iPhone SDK, so seeing it within XCode is a promising move - even if the possible use of Digital Signing in an iPhone SDK is pure conjecture on my part.
  
• Front Row now sports the Apple TV interface, and the integration with the Apple Movie Trailer site.
  
• iChat has seen a smorgasbord of new features added - Photo Booth effects, new media codecs, video and audio chat recording, tabbed chats, the ability to hide your own local video from a chat window, and screen sharing.

• Hypercard
• ArcInfo
• BBEdit
• Freehand
• ArcView

• All Finder windows are set to column view. Seriously, icon and list view are just infuriating to me at this point. I don't know how I used list view so happily for all those years with the "classic Mac OS."
• The desktop bears only one single icon. That icon is the hard drive. I cannot understand people whose desktops are so littered with icons that the desktop picture is barely visible. I don't know how they find anything, or even focus on the screen. I'd need a Ritalin smoothie to use that machine.
• The Dock is transparent and borderless. I started using TransparentDock a while ago, and now the sight of a white Dock just irks me. Speaking of the dock...
• The hard drive and Applications folder are in the Dock. But that's a given, right?
• Quicksilver is installed. That's right, I can't use a Mac that doesn't have Quicksilver installed. I find myself hitting Command-space on other machines all the time, as it's ingrained in my muscle memory at this point. I can hit Command-space-m- (for Mail) Return without even thinking about it.
• I have a two button mouse. Just try it for a week, you'll never go back.