Google has posted a SEO Report Card on how well it’s own sites are optimised for Search Engines. The Report card examines the on-page optimisation of the various components such as Titles, Descriptions, URL’s, Headers etc and shows how various Google products are doing it well and others need improvement.
An excellent video by Matt Cutts of the Web Spam Team at Google. He explains the basic of how Google search works including page rank, relevance, reputation, keywords, importance of posting daily and understanding and communicating your readers.
The main changes are actually behind the scenes, where we have changed from Microsoft .NET based website to a WordPress based site.