Problem solved! I'll explain my experience so hopefully someone can learn from it. I tried everything possibly suggested on these boards about running cron jobs and modifying my db values for statsmaxruntime, and enabling statistics, etc. Nothing worked. Until I tried going to Site Administration > Development > Debugging and turned on Debug messages for DEVELOPER, and toggled the switch to Display debug messages. Then I ran cron.php from my browser and got a fatal error. Previously cron would run, but no errors were displayed, so I had no idea that it wasn't getting all the way through the script. The error message that was displayed showed me that there was a php error in one of my custom theme files. I never would have suspected a theme file (config.php) would keep my statistics from being gathered properly. I fixed the php file and the next time I ran cron all of my statistics were generated properly!
I realize in hindsight that the error did relate to my 20121112 upgrade, in that my theme is based off the afterburner theme and when I did my upgrade, the afterburner theme was upgraded and even though my theme files were in a different, renamed folder, I had not properly renamed the references to the original afterburner style sheets. Without renaming some of the references within my php files (and subsequently renaming css files that I was using), there was a conflict between the two themes on my system.
In short: If your stats aren't being processed properly, try turning on the DEVELOPEER Debug messages, then run cron.php and see if you get any error messages.