For those of you that have not already done so, you should check out the geeky discussion going on a Matt Lombard's blog at:
Not sure if any of that discussion helps clear the mud, but I hope so. Let me know what you think. It seems that it will only get more confusing as history-based technology adds more powerful direct editing and dynamic feature manipulation, and as direct history-free modeling adds more intelligence to the B-Rep.
The Big question is; what does it all mean to the process of designing products? It will certainly be interesting to watch.