Today’s post dwells on the discussion of link buillding tactics that influence search engine ranking factors in 2009. Link acquisition is a key component of the ranking algorithms. The number of external links pointing to your site and the anchor text contained therein can certainly propel your site to the top of the search results pages.
I will be discussing only the top 4 factors under each section with a mention of the value score allotted by the SEO professionals . This biennial survey by Rand Fishkin at SEOMoz picks the brains of the top 72 SEO professionals from all over the world and their collective wisdom is presented in this post.
I) Link Building Tactics For SEO:
1)Link Bait And Viral Content Creation: 67% Very High Value
Just as all links are not created equal, all content created on the web is certainly not equal. There are certain pieces of content that are so well researched and presented in an interesting fashion that most readers fancy and take a liking to. They end up distributing it across the cybersphere through social media networks and emails.
The virality aspect is in the nature of the content itself, be it a 400 word ingenious piece titled
“10 ways to [solve a specific problem faced by people world over]” or a catchy video that captures the imagination of users. A recent example that comes to mind is the babies skating around in their nappies in an advertisement for a French water brand.
All this results in a massive surge of backlinks to the site which published this piece of content. There is a huge spike in traffic to the original website. The search engines love the natural scheme in which the backlinks are generated. Users follow links to read/watch the content. It is a win-win situation for all.
2) Blogging And Engagement With The Blogosphere: 66% high value
The influence of blogging cannot be stressed enough in the cyberworld. It is an incredible way for a “domain expert” to share knowledge and get valuable feedback from readers in the form of comments. Blogging is a long term process and it takes time and effort for a blogger to establish a good relationship with her readers and fellow bloggers in her chosen niche.
The popularity of a blog can be ascertained from the number of readers subscribed to the RSS feed and the activity taking place on the blog itself by way of exchange of comments between the blogger and readers. Over time, the blogger earns the reputation of a respected authority in her domain and develops a loyal band of committed followers.
The high quality and originality of her blog posts will result in posts getting tweeted over Twitter and passed around other popular social media networks. Each mention of the post on the web is a vote for the source site as far as search engines are concerned. Atleast, a tweet on Twitter ensures that the post is indexed by Google which scours the Twitter landscape actively even if the traditional blog and ping service is not being used.
Being a guest blogger on other popular blogs in the same niche or participating in blog carnivals can bring lot more exposure and hence traffic to a niche blogger’s site.
3) Classic “Create Valuable Content” Strategies: 58% High Value
Content that is original and written in a polished style stands out amongst the fluff that floats around in the cyberworld. Most times, it is borne out of practical knowledge of the author in a particular niche. As the saying goes – “Knowledge borne out of experience is wisdom”, the same goes for content that is written based on experiences gleaned by the domain expert through day to day application of the techniques described therein.
4) Public Relations: 56% High Value
Press Release (PR) is the first thing that comes to mind when public relations is mentioned. This is a powerful tool that can generate great backlinks and mentions if executed correctly. Traditionally, press releases that are interesting and absorbing catch the eye of journalists covering that niche who in turn refer to it in the news column they author. The higher the status enjoyed by the newspaper, the wider the exposure gained by the press release.
Sadly, this powerful tool has not been wielded well as a many press releases end up being pretty much self hype harping on the virtues of the company and the owners rather than dwell on the important part – the uniqueness of the product or service offered.
Beyond press releases, Jessica Bowman states that public relation departments and agencies are not up to speed when it comes to maximising the opportunities for search engine rankings.
II) Factors Affecting Value Of An External Link:
1) Trust Of The Source Domain: 70% Very High Value
The trustrank concept is based on the fact that good and trusted sites are linked together at the core of the web and that spam pervades outside this central area of good neighborhood. It is based on a Stanford University research paper titled Combating Webspam With Trustrank 
The search engines caluclate Trustrank as an iterative Pagerank type of metric that flows link juice from a bunch of trusted seed sites to determine if a domain is trustworthy or not.
Another way of looking at it is the number of hops the domain in question is away from the trusted seed site. If it is within a limited number of hops from the seed site, then it can be considered to be high in trust. My earlier post titled Relationship Between Trust and Link Building  talks about this aspect at length.
If this cannot be determined algorithmically, there is a possibility that human reviewers could confirm this aspect by looking at the percentage of links to and from a domain that link to good neighborhoods and bad neighborhoods.
2) Global Authority/Importance of Source Domain: 68% Very High Value
The authority of the source domain is an important criterion that adds more value to the quality of the link emanating from it. The domain authority is a hybrid combination of the quality of links coming into it, domain trust and age of the domain.
The quality of links is influenced by the links coming into a site from other powerful well trusted domains. The strengthening of the good neighborhood aspect is vital to the good ranking of the site in question on the SERPs.
3) Keyword Anchor Text Of The Link: 67% Very High Value
The words that form part of the clickable link is generally referred to as the anchor text. Typically, the anchor text confirms to the search engines the nature of a page with respect to its content and whether the link that describes the page in question really is representative of it.
Internal linking within a site gives a good idea of the nature of the content to search engines. But it is the anchor text in external links that really reinforces the initial confrimation of the search engines. If you have a great article on blue widgets, then the inbound links from external unbiased sources that have blue widgets as part of their anchor text provides a lot of value to the recipient site and goes a long way to help it get ranked well in the SERPs.
The context in which the link appears on a page is also vital. If it is an editorial link from an external site where the author writes about a certain topic and contextually links to an article on your site, it clearly shows Google that your article is a great benchmark in that particular niche and one that often gets referred to in other posts and articles on the web. Such natural links have the highest value in Google’s eyes and these links are equally hard to obtain.
4) Quantity of Pagerank Passed By The Link: 59% High Value
If a page has a Pagerank of 5 points and if there are 5 links going out from that page, then each link ideally gets 1 pagerank point (Pagerank of a page / number of links on that page), provided none of the links going out of that page are nofollowed.
If your site gets an editorial link on a highly trusted strong domain page with high Pagerank, the amount of link juice passed by that link to your site is quite high and your site gets the ultimate benefit from such a link. Such a high quality link can be considered equivalent to a few hundred links from mediocre sites.
From the observations of many seo gurus in the past, it is ideal to have 100 or less links typically on any given page in order to distribute the pagerank as fairly as possible from the home page to the category and sub-category pages.
Search engines nowadays tend to ignore the navbar and footer links to a large extent. It is clear that the position of the link on a given page is important to be considered in the link graph calculations of the site by the search engines.
Instead of using nofollow links, a site owner can design her site in such a way that the important parts of her site are given prominence in the site architecture hierarchy and page consolidation is done for less important areas of the site.
For a detailed account of all the link factors that influence search engine rankings, Rand’s post titled
Effectiveness of ilink building tactics for SEO  is an illuminating read and can whet your appetite for more knowledge on the ubiquitous links that form the basis of the world wide web.
Ravi Venkatesan is a senior SEO consultant at Netconcepts, an Auckland search engine marketing company  that provides both seo services  and pay per click services  to its clients New Zealand and Australia wide.