Hi. I implemented this hint as instructed, but it never quite worked as advertised. Time Machine would not start backing up at the requested interval (whether this was 24h, or 2h). I then went back to the original setting of 3600sec, but now Time Machine would not even do the normal hourly backups anymore! Only manually could I initiate a backup.

I tried deleting the backup database, changing disk, and starting from scratch. Then, while fooling around with Time Machine, all of a sudden I had a file corruption issue in an important Microsoft Word 2008 doc, and as a result have now lost 1 week's worth of work. Thank you Microsoft, and Mac OS X Hints!
Yes, I know the usual disclaimers. This time, they really have proved justified. I've been burned, and I shall never again implement any Mac OS X hint in my life. I will leave all system settings exactly as the manufacturer intended.
One last favour to ask from the Mac OS X community: how can I make Time Machine behave as normal again? - it still wouldn't do hourly backups. And all of this because I changed one numerical value in a plist file... Nightmare
Thanks for your help
Robert