I disagree on the misspellings in the keyword tag. If you use the tag at all (I don’t) you want to make sure the tag is “inline” with the rest of your content. Meaning make sure you put in keywords in this tag that are on your page. A red flag for the SE’s is putting keywords in their that don’t match the content of the page, description tag or title attribute. I have tested this on Yahoo and it makes a big difference.

Either way I simply don’t use the keyword tag to avoid issues. I will use the keyword tag if it helps with internal search function of the website.

As an SEO old-timer, I use the keyword tag out of habit. I figure it can’t hurt if used correctly. There was a time that I included misspellings in the tag, but have more recently found evidence that not having words that you include in the keyword tag actually on the page can be a red flag, at least with some engines. I tend to agree with incrediblehelp and always make sure the words I use in the keyword tag are actually on the page.