It would be nice if the axes were labeled -- that would turn the chart into something other than a pretty picture with no meaning.
Not really -- for both graphs, a specific numeric value is given based on the mouse position, but not what information the graph is meant to convey.
Also, in a tablet, you can point at the chart with your finger and get the same information. Or, in this case, the lack of information. :)
EDIT: I just tried this chart on my tablet and you get the same data by pointing.