It looks like they have been in the engine for a while, mixture is a little rich, and looks like you are burning a little oil. I would have to feel the black soot around the ring of the plug to tell, sometimes I wipe it on a piece of white paper. dry black is rich soot, oil is a little wet, to the touch..
You can tell a lot or a little from reading the plugs, depending how you do the procedure. WOT clean cut off, on the dyno, or at the track tells you the most. And a fresh plug each run. I am a tight wad, when tuning, a lot of the times, I will just put in one plug new each pass, until I get close. From the heat mark on the strap, the timing is close, maybe could use a couple degrees more. If you are rich at idle, the soot will cover over the WOT marking, by the time you get back to the pits.

On my drag car, the plugs read a little rich, when the O2's are at 12.5, the plugs start to turn tan colored, when, I read 13 to 1, I guess it is the placement of the sensor in the collector. Nothing is 100%, I just look at how many tools to get it right. Of course the time slip is the final proof, of how it is running.