Almost gave up on Ubuntu due to serious wireless frustration issue, but decided to upgrade to see if that helped shake out whatever it was.
Happy to report that Ubuntu now picks up my WAP much more quickly.
However when I get prompted for the keychain password (and enter it correctly), it rejects the password. I get around this simply by clicking the 'Deny' button and I authenticate to the WAP right away.
Probably a simple fix, but I'm flummoxed.