Ranks are based upon an algorithm that takes into account quite a number of things, not all of which are point earning activities. We do not reveal the formula but we look at a lot of things. Your follows, quality of your contributions, and just a whole number of things that are not necessarily reflected in the points will count towards your rank. We do not reveal the formula as we don't want people to game the system to gain Ranks.
Activity level titles are different. You can see your activity level titles defined in your Recipes under Milestones, and they are based strictly upon points earned. You can see how a user gains points via the points formula, though a user's points total can be added to or subtracted from by recipes that reward popular content or punish bad activities.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .