I you can please click on the link to view pictures of my #2 sparkplug and try and diagnose what is causing it to look like this. Plug has 10k on it and the plug I took out and replaced looked the same way. All other plugs except #3 look like normal burning plugs. See why #3 is the exception HERE

Fixed
Link to plug pics HERE

 

Plug link no worky, says I need a logon

 

Next time you need to put a link from the community page to the photo.

Here is the link to the album for the rest of us:
http://community.webshots.com/album/248362596sjBfPr

 

Someone correct me if I am wrong but that looks like the beginning of coolant getting into the cylinder. I would replace both headgaskets again (since you are already doing one from the snapped plug) and that should take care of any issues in that cylinder. Also soak the intake valves in top end cleaner overnight (but do not remove them) and then pour that out and use some carb cleaner to follow up and remove all the carbon that was there (if there is much at all). Should run better all around after doing so.

 

I fixed the link to the pics forgot that I needed to do that.
I looked at a bunch of pics on the net today and I think it was oil getting into the cyl. I did the dollar bill trick at the tail pipe and it was getting sucked in.
I have the 22RE so only one head to take off and it is done. The #2 exhaust valve has the same discoloration and burnt on stuff. So the head is out and there isn't anything obviously wrong with the gasket, but it will be changed now, along with the timming chain and front main seal.

 

I would also guess coolant for what its worth.

 

It turned out to be oil leaking past the valve seals. The #2 exhaust alve seal was missing the top and oil was pouring into the cylinder.