Good point about Itanium, but that doesn't mean people have problems writing dataflow languages. It's more about the compilers, because very little of the code we run is written in assembly language. Any new architecture will have to gain adoption by having a C compiler.

There were high level dataflow programming languages, like Lucid: http://en.wikipedia.org/wiki/Lucid_(programming_language)

And there were academic dataflow computers as well.

I think D 2.0 makes everything immutable by default (single assignment), so it is close to a dataflow language. And that's no surprise, because Walter Bright designed it specifically to make writing a compiler as natural as possible, rather than having to make complicated inferences about serial code.

My point was that we can never make the jump because the stack of hacks we currently have works "good enough" and it is backward compatible. Generally technologies evolve by accretion, and I'm hard pressed to find an example of radical simplification.

I guess power concerns would be the only hope for something simpler.

It's kind if funny that Backus wondered, "Can programming ever be liberated from the von Neumann model?" This question also applies to hardware too.