There's been talk about this on Reddit too, where our chief architect of QNX 8 broke down the decision. He mentioned it was ultimately a tough decision, but that in the end the cons outweighed the pros.
Such decisions should always involve the customers. A chief architect that knocks one of the foundation stones out from under a building isn't doing the bureau they work for any favors.
Hey, could you please post a link to the thread you're referring to? I'm guessing it had to do with the io-pkt to io-sock transition, but I couldn't find any information about that.
I've also noticed that all of the message passing system calls still accept the node ID. Are there plans to open up this interface to allow for implementation of custom network managers, maybe? I'd be very interested in exploring that.