So those controls in the last link can be displayed in the workbook as views on command output? I've been toying with a similar idea for a while now - wasn't aware that there were already implementations of it. I think we're going to witness/participate in a paradigm change in the near future.
Also check out http://www.wolfram.com/cdf/ for the more general attempt to make a dynamic document standard. I don't know how successful that's been.