I will often use ratios in my tables and I would like to be able to allow a user to point at a value/cell and see the tooltip of the numerator and denominator so they have a frame of reference rather...
Having it for table values by column would be ideal -- if Matrix visuals already support this (albeit not a clean implementation), then why not Table visuals? Furthermore, to have even column specific header tooltips, like Excel's comments, would be invaluable to end-users.
