In 5.0, no item is selected after a mail search.
Old thread, there's some new options in 5.0.6/.7:
Preferences> Mail > Displaying Messages > When I read a message in the reading pane:
-Mark it read immediately
-Mark it read after x seconds
-Do not mark it read
The user is not using the read pane. That's the problem. She doesn't like it and double clicks on her messages to open them. They don't marked read until she clicks on Read Mail after. It may be a bug since it happens only about half the time.
Hey just incase anyone has Still not found a response to this.. i was messing around and when you right click, a menu show that you can use keyboard command to mark multiptle items as read.
use [mr] press m & r key together and that can help the problem aka Mark as Read or [mu} to keep as Unread
hope this help for any one that still needs it, if you found it already, sorry for the repeat..