Upgraded my 2010 Macbook pro to mountain lion last night, so far its great. Just signed into Twitter, and in the share button on safari and other places there the twitter option, however in the notification bar there isnt the compose tweet option at the top! do i need to activate it somehow? or is it something that my older mac "can't handle" ???? would be really annoyed if it was, really angry about not being able to mirror on my apple tv any hell would be appreciated thanks!