Having watched the video on MSNBC I have a question (I am a fixed wing PPL student of 4hrs so far).
Greg Freith (the former NTSB guy) stated that the piper flew into the path of the helicopter - in the UK the presedence is to give way to the right so would the chopper not be in the wrong - is this different in FAA land? (This question is not to apportion blame but to understand why he said what he did).
Regardless of what aviation law says, I find it hard to believe that in VFR conditions if either had seen the other that they would have proceeded on a heading without observing what each other where doing (as in you would always work on the basis the other has not seen you).
A very sad incident which is another expensive lesson in life which hopefully has the silver lining that we learn from it.