Just a very short message to direct you to my article on statistical significance over on the Kissmetrics blog. The emphasis is on intuitive means to understanding the key ideas.
Check Out My Guide to Statistical Significance on Kissmetrics
Fun, example-filled guide, aimed at building intuition
Rich snippets and all the basics about keywords in title tags, URLs, etc.
A High-Level Catalogue of The Main Areas to Fiddle With When Optimizing Your Conversion Rate
Separate language from territory; clarify your international site structure to Google