Pulled plugs yesterday after oil change and found this. I'm no expert but this can't be good. I recently swapped out carbs, and put the boat in the water once for a couple laps. Plugs shouldn't look like that after a couple of laps should they? Grant it, I did not pull the plugs to see what they looked like before carb change, guess I kinda have to take that into consideration. I'm kinda confused now to see if I need to change the jets or not. Boat ran fine (well... ok) with old plugs. Hope to be on the water to do a plug read to find out which way I need to go.   

you cant read plugs like that, you need to install new plugs then run wfo and shut it down. no idle

x2 but you might want to take a look/reduce your jets and/or adjust air/fuel for your set up.
http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

Thanks for the link, it'll help out quite a bit! There are new plugs in the boat, and changed the primary jet. Gonna throw in fresh fuel, and fuel treatment to see if that'll clear up a lot of carbon deposit.