Doesn't help you much when the vote is split 50/50 (at the time I wrote this).
June is a little more tempermental weather wise, but it really depends on what you want to see. There are more whales earlier in the summer but they may still be there in August. If you want to see the Salmon run (bears eating them) then August is your best bet.
We went mid June and it was nice. the temperature varied from 50 to 75 degrees. average was about 65.
Carnival Cruise Lines:
Fantasy 90, Celebration 95, Victory 05, Conquest 05, Spirit 6/06, Freedom 6/08, Holiday 7/08, Victory 6/09, Valor 9/09, Dream 6/10, Splendor 8/10,Conquest 8/11,Magic 11/11,Triumph 4/12,Spirit 7/12,Freedom 11/12, Triumph 2/13 - The fire cruise
NCL Dream October 2006, RCCL Mariner OTS June 2007