One critical thing in today's social networking world is to take a critical look at your Facebook and Twitter (and other?) accounts. Take a really cold, critical look. See them as a responsible employer might see them. See them through the eyes of someone who is thinking of paying you thousands of dollars for your skills and service. See them through the eyes of someone who is enormously invested in having a well functioning, well governed workplace where employees will be seriously focused on the tasks and projects at hand. See them through the eyes of someone who does not want harassment or bullying or vulgarity on ethnic, racial, sexual, gender, disability or on any other grounds. Not only are these things disruptive; not only are these demeaning to others; not only do these things stir up enmity between workers and cost enormous amounts of money in lost or poor productivity, but these things are also illegal.
Now that you've taken a good hard, cold, objective look at your accounts, if you think you would not hire you; if you think you would not trust you to keep the peace and integrity in a work place; if you think you and your friends sound like immature, vulgar, ill-mannered misfits (though you love them all dearly and they love you to distraction with utter devotion); if you think there is a chance an employer with thousands of dollars and hundreds of training hours at stake would be hesitant to trust you and hire you, then block or close your accounts.
Unless your friends are going to financially support you in the manner to which you think you should be accustomed; unless you think love is thicker than income, the first and most important thing to you is securing a job. If your accounts might stand in the way, block or close them before they do. People are routinely denied jobs because of comments and attitudes expressed by the person or their friends on Facebook and Twitter. People are also routinely fired for the same reasons. So to prepare for a job interview, block or close anything that fails to represent you in a respectable manner. After all, an employer must first respect you in order to hire you.