Current FacebookMeResponse class in Skybrud.Social doesn't expose an email property. Using this little hack the email adress can be obtained given that the Facebook app can access the email of the user.

FacebookMeEmail.cs

// Get the raw string
string response = service.Methods.Raw.Me();

// Parse the JSON
JsonObject obj = JsonObject.ParseJson(response);

// Parse the JSON object (use as normal)
FacebookMeResponse me = FacebookMeResponse.Parse(obj);

// Get email
string email = obj.GetString("email");