Just upgraded and everything seemed fine. However, I just discovered that my iMessage status in the menu bar is 'Offline' and when I try to click 'Available' nothing happens. In the iMessage app, the 'Messages>My Status' menu items are all dimmed. I have confirmed that the correct me.com account information is listed in the preferences, and also that messages sent via my computer are synched with my iPhone. However, nothing is coming in. One more thing: there used to be a synch button in the menu bar, but is no longer there - is this normal?