META Keywords and Description Tags
I know, I know… Old news. No one uses them anymore. Well, I don’t care. I want them in sites that I create (though I don’t use them for this site). I did as much research as I could to find the best way to implement them. Specifically, I was looking for standard limits on the number of characters or keywords that one should use. Let me just say that the information is not easy to come by. Most every site that has advice on the topic has conflicting information.
For anyone who cares, it seems that the safest bet for keywords is a limit of 15 to 20 words if possible, separated by commas. I could not find a clear character limit for this, so just try to keep the words reasonable.
As for the description, 180 characters or less, including spaces, would be a safe bet.
Here are a few articles and forums upon which I have based my conclusion:
http://searchenginewatch.com/webmasters/article.php/2167931
http://www.globalserve.net/~iwb/search_engine/killer.html
http://www.webmasterworld.com/forum5/5671.htm