Also, Stefan Tilkov is momentarily a binary messaging bigot.
AMQP is a young upstart. Perhaps it will break out. I'm just saying it will be hard. It is really hard to get a protocol going. Time will tell I suppose.
At the end of the day, IBM MQ Series/WebSphere MQ still has over 90% of the messaging market last time I heard so in terms of application integration within the "enterprise", I'm putting my money on that continuing for the foreseeable future.
Perhaps overtime, AtomPub, XMPP, and HTTP can put a dent in that.
The whole pub/sub business may be an opening. MQ Series isn't known for that. They have a new 100% Java version that I presume does a better job. XEP 0060, AtomPub, etc. could be alternatives.
In the short term, I think that ActiveMQ has the best chance of taking on IBM MQ Series/WebSphere MQ in terms of the more classical messaging stuff. But then again, I guess that may be ok with IBM as they support Geronimo which includes ActiveMQ.