...9:10 am EDT Sunday March 4, 2012....
...so Apple DID call me back to update me on my error report:
Apple engineering is aware of the problem and realizes it is a problem on their end...not a user error or a user fix.
There is no exact timetable for finding/fixing/releasing-a-patch but Apple working on it.
My own observation:
I was able to refresh the category 'Eclectic' which I have not been able to do for over a week. Someone earlier suggested that I drag my radio station to the sidebar (or you can put it is a playlist). THIS IS A GOOD IDEA AND IT WORKED FINE.
I notice that after I refreshed 'eclectic'--and other genres--there is now a station count in parentheses, e.g., "(364 streams)". It's always hard to say what causes a bug until you look at the code and find it, but something likely got changed in the last releas of iTunes that caused this bug.
Apple does acknowledge the error and is working to fix it--the support desk/Apple Care was VERY helpful and informed. I'm going to spend a nice day with my family.