macjack,
I posted the same question in a couple other Apple Forums.
A comment in another thread suggested that the growing backup was not caused by TM, but by a file or program, and suggested I do several backups, and use the free app "Time Tracker" to compare each of the backups with each other to see what was actually backing up... Another comment was that, even though the TM Backup was not showing up in the excluded list, it was indeed being excluded by the TM software.
After running backups all night, and comparing them with Time Tracker, it appears my iMac was backing up normally... However, I have an external drive that I use for an iPhoto library, which is about 450GB in size...Turns out the "incremental backup" file was my external iPhoto Library HD.
Normally (if I'm looking at the Console), I'm able to see that external HD's name and size of backup that's going to occur. For some reason, when Time Capsule would attempt a backup of the iPhoto Library, the Console would not show the external HD as backing up. Also, it seems that TM did not calculate how big the backup of that external HD was going to be... In the TM Preference Panel, I'd see a small backup of "something" that gradually got bigger and bigger... That, combined with the fact that it didn't appear that my TM Backup was excluded, helped me to grab hold of a red herring (so to speak)...
And now, several backups later, everything looks, and functions normally (with the exception that I still can't see my TM Backup in the exclusion list)...
Thanks again for your help!
Red-Herring-Bob
