Well this one freaks me out.
I used a Http Header check tool to check the headers of my webpage and guess what.
In every request the response was 302 instead of 200.
You are getting this because .net/IIS redirects your www.domain.com or domain.com to www.domain.com/default.aspx, so you get a header with 302 and then one for 200. I think this is by design but very confusing.