My web site also uses popular social media widgets, like the Facebook "Like" button. Social networks like Facebook collect data which they share with third parties and often do not disclose the specifics. If you do not wish to be tracked by social networks consider installing browser extensions like Ghostery or DoNotTrackMe (available for Firefox and Chrome).
Comments on my blog are made public. Like all webmasters I can see the IP addresses of the visitors and may use this information to block those who abuse my blog.
When you use the contact form or comment on the blog and fill out the "Email" field I can see this email address but will not publish it. The email address allows me to display your avatar image by calling it up with the encrypted email address (if you have assigned it to your address using the Gravatar service). I will never disclose your email address to third parties and may use it occasionally to contact you personally. If you subscribe to automatic updates by email you will have an option to easily cancel the subscription.
If I can answer anything else please just ask using the contact page. I hope you will enjoy my web site!