A friend of mine who has a PhD in Geology (not exactly a related field, but eh) and is interested in the Voyager program was telling me about this the other day. Basically, it's not that these measurements give us any new understanding of the universe _by themselves_; but, they may (and probably are) confirming theoretical models we have about interstellar space, providing more color and texture to other observations, and improving our understanding through increased richness of understanding. In other words, extremely useful but not in obvious "here's the smoking gun" ways.