There seems to be a lot of misconception in this thread about state, why it's complex how it can be fixed. Some quotes:
He seems to think it's something called "managed refs" and that sounds like some kind of dog shit you'd find in .NET to me.
As >>39 points out, state is just a fact of life. There's nothing inherently complex about an integer or a function that increments an integer in place.
There is actually another presentation from Rich that explains all this points:
http://www.infoq.com/presentations/Are-We-There-Yet-Rich-Hickey
I recommend you to watch it before discussing any further here, because at this point the thread has degraded completely into empty talks about assembly, CPUs and other irrelevant bullshit.
Also, I think this talk is even more informative and insightful than the one from this thread and I'll create a separate thread for it so more people would have a chance to see it.