links, one way links, reciprocal links (2)

As a conclusion after the link popularity studies, here's my view on it:

1. more links to relevent sites with rich content, and good PageRank.
2. a little link exchange is acceptable, but dont make it over half of your links
3. limit the max number of links to 80 in your link page. Split it if too many.
4. a better appoarch to gain link popularity is by writing ezine articles.

BTW, my pagerank is still 0/10. Anyone can help me get rid of the null score ? >.<