Keyword is a very important factor for a site. We should select right key word or phrases for a site, so that we can get some loyal visitors from those. After we complete the keyword selection, the next big task is target right keywords for right pages.
Sometimes people are targeting too many keywords on a page, which we shouldn’t do. Now the question is how many keywords we should target for a particular page. If you search on the net, you will see that different people have different ideas and opinions.
Nice explanation by Rand Fishkin here at seomoz.
You write very well.