Jools I don't see where anyone actually mentioned anything about the keywords metatag. The leading SE's don't even bother with them anymore. They give precedence to the title and description tags. The keyword metatag not withstanding, there is no optimum number of key words, just use as many as you can in those two tags and be sure they also appear in the body of the webpages.

As for the actual keywords metatag, I guess I'd still use one, but you have to be sure that much of what's in the title and description tags should also show up in the keywords tag and its words should also be in the page body.

As for size, just do some searches on that and come up with the average of what you see because each site you go to, each answer you get, is going to be different. Just remember to use as FEW as you can while still covering all the words, because the fewer you use the higher value is given to each word. This is true with all of the tags.

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Happy Thanksgiving to all & God Bless,
-Clint
(Join Date: 2003)