Ihave check many meta tag anylyzer. And trust some time the result are pathetic. Instead of guiding me it has always misguided me. Some Give me keyword relevency of 80% some give me 50%. So dont understand what to do. Some how i have managed to get my site listed on yahoo 27 position for adsense help as keyword and on 5th page of google. But i seroiusly do not understand what is right amount of keyword you can use in meta tag
You should be aiming at around zero keywords, that should give you a relevancy score of 0% and a density of around 0%. Google doesn't use meta keywords, And neither do any of the other big engines. They are a complete waste of time and you should be spending the time you waste on "tag analyzers" doing something more productive.
I wouldn't say that considering if I take out a keyword from the metatag then a few days my rank drops. I use 9 and I'm winning the battle with them all except 1 of them(the tough one). The thing is I didn't start off with all of them. I only had 3 of them and optimized for them, then gradually moved into new keywords. I'm thinking 11 keywords is close to max before search engines will not be happy.
If you did see a change in rank it was a coincidence and not caused by the removal of a meta keyword.
Keyword are useless. I use http://www.widexl.com/remote/search-engines/metatag-analyzer.html for the other tags, sucg as title and description It is giving great results.