I also have a question re: the unsubscribes. How come where the reports show recipients haven’t clicked and they haven’t opened the email but they have they unsubscribed?
How is this possible?
An open is recorded when the tracking image is downloaded, or a content link is clicked. If someone looks at your email without images being loaded, and just clicks 'unsubscribe' then they are removed - see http://www.campaignmonitor.com/blog/archives/2007/01/all_about_email_open_rates.html for more.