yum update
It went through the paces, eventually downloading 10 packages after several mirror changes to get the total set. It then presented me with the command line prompt. Apparently it did not do an update, since RHN still indicated a need to update. I ran up2date and it went through the normal process, downloading and installing the updates. RHN applet is now blue again.
Previously I remember that after a yum update, the RHN applet would turn blue, and it it didn't, asking it to check for updates would satisfy it.
What happened?
Gerry