We remember there were pages stuffed with targeted keywords once upon a time as people assumed the more number of keywords on a webpage the better it ranks. And now days we have seen Search Engine Optimization Experts recommending to keep the count around 2%-5% etc. Again we feel all these are irrelevant. A writer needs to concentrate on producing a effective writeup and should not even think at the back of their mind if increasing or decreasing the words would matter their search engine results.
Recently we come across blogs and articles from eminant personalities saying W3C validatation does not play a role in ranking websites high. Even Google's Matt Cutts clearly cited validation is not considered as a ranking factor (Why doesn't google.com validate?, Is HTML validation necessary for ranking?).
When we do keyword research it is necessary to identify the intent of the searcher in order to target the right keywords. Andrei Broder of Yahoo identified three types of searchers based on the search queries they make.
These searchers try to reach a known website but they do not know its exact domain name.
Theses searchers try to find information about a new subject or are researching additional information
I had a nice discussion with one of my friend where we discussed if W3C validation plays any role in ranking a website higher in the search engine. Please find below parts of the edited chat.