Hi everybody :)
The one way that I have found to effectively clean any goo off my iron is to plug it in, set it on cotton, and pour a teaspoon or so of regular table salt on a folded section of newspaper. Run your iron over it until the goo is all gone. Cost efficient and it doesn't harm your iron, or it never has mine. I do not have a teflon coating on mine however, so you might want to use a little caution there. I really don't think it would be abrasive enough to harm it though. Just keep the salt under the iron when you are cleaning. All you have to do is raise one side of the newspaper or the other to get it back in the middle. Just take an old toothbrush to get the excess out of the steam holes.
Anyway I have been keeping myself entertained looking at all of your pictures of all of the beautiful quilts. You are all doing a super terrific job. Keep up the excellent work.