I now use Vigilance. http://lornareiko.wordpress.com (my experimental blog)
I used my experimental/practice blog to see how it would look in the 2010 theme. After doing so, I lost everything in the right sidebar other than the Search and the Calendar!
After some scary heavy breathing, I went to Dashboard>Themes, reactivated Vigilance, and then all of the items in my right sidebar reappeared. (Whew!)
I conclude that if I switch my main “real” blog from Vigilance to 2010, I will similarly lose everything in my Right Sidebar. Yes or No? If no, then what's going on???
The blog I need help with is lornakismet.wordpress.com.