The Messages app still isn't something I'd consider beta quality.

Messages show up and seemingly random times on all devices. Sometimes, they don't both to show up on a device (typically the Mac). Sending still works fine, until over the weekend, when I became unable to initiate iMessage conversations on my Mac. I'm told that the other person is "offline", while I'm having a conversation with them on my iPhone.

It's really bad. I hope there have been some fixes, but since I'm running "Gold Master", maybe not.