Matt Cutts from Google has mentioned that there areover 200 variables in the Google Algorithm that effect how your site shows up in their engine. Here are the top 50 that I could find:
Domain: Age of Domain, History of domain, KWs in domain name, Sub domain or root domain, TLD of Domain, IP address of domain, Location of IP address / Server
Architecture: HTML structure, Use of Headers tags, URL path, Use of external CSS / JS files
Content: Keyword density of page, Keyword in Title Tag, Keyword in Meta Description (Not Meta Keywords), Keyword in KW in header tags (H1, H2 etc), Keyword in body text, Freshness of Content
Per Inbound Link: Quality of website linking in, Quality of web page linking in, Age of website, Age of web page, Relevancy of page’s content, Location of link (Footer, Navigation, Body text), Anchor text if link, Title attribute of link, Alt tag of images linking, Country specific TLD domain, Authority TLD (.edu, .gov), Location of server, Authority Link (CNN, BBC, etc)
Cluster of Links: Uniqueness of Class C address
Internal Cross Linking: No of internal links to page, Location of link on page, Anchor text of FIRST text link
Penalties: Over Optimization, Purchasing Links, Selling Links, Comment Spamming, Cloaking, Hidden Text, Duplicate Content, Keyword stuffing, Manual penalties, Sandbox effect
Miscellaneous: JavaScript Links, No Follow Links
Pending: Performance / Load of a website, Speed of JS,
Misconceptions: XML Sitemap (Aids the crawler but doesn’t help rankings), PageRank (General Indicator of page’s performance)
