As far as I can see the graph/stats are the same as V6, and are equally as criptic. So, the answer for dagar is: No, there are no changes in the graphs/statistics.
It would be helpful for the graph pages to have some notes on how the values should be interpreted. The legend is nice but provides no context of how the values should be used.
Further, graphs/measurements based on "bytes" level scaling and not "KB" or "MB" have little value in modern storage systems where storage in measured in TB and disk/Network IO in MB!