consider   consider the following facts before submit :-

              Static Text Links 
              The Age of the Directory
              Cache and Sub-Pages
              Directories Search Results (in Google, Yahoo! and MSN) 
              Rankings for specific topics
              Quality of sites listed 
              Quality of backlinks
              The directories goals 
              Keywords permitted 
              Search Engine Friendliness 
              Relevance to your site

              These sites are for study daily updates in SEO.

              Google Blog 
              Gray Hat Search Engine News 
              Jeremy Zawodny's blog 
              John Battelle's Searchblog 
              msnsearch's WebLog 
              Pandia Search World
              PassingNotes 
              ResearchBuzz 
              Resource Shelf
              Search Engine Blog 
              Search Engine Guide
              Search Engine Lowdown
              Search Engine News Blog
              Search Engine News Journal
              Search Engine Roundtable 
              Search Engine Watch 
              Search Engine Watch blog
Traffick    Threadwatch.org
              Abakus SEO Blog
              webmasterWorld
              webProNews                              

              These site give you the best and updated knowledge about SEO.