Well, that doesn't explain much. What makes it an important part of the 'pedia? LDan
If we are to have some sort of standard of importance, notability, or relevance, then the best way to define it is through examples applicable to the various fields of study.
To some extent this has been done, with an effort under way to merge articles on places with fewer than 10 people, and with the "Criteria for inclusion of biographies" page.
Some Wikipedians claim that any such standard is pointless and that the only thing that matters is verifiability. I do not necessarily adhere to that view, though I think there are more pressing matters at hand that can be more readily solved.
One alternative would be to take a slashdottish approach and assign "relevance levels" of 0-5 to each page. Pages below a particular user's "relevance threshold" would not be shown. Just a surface thought.
Louis