You do have some element of control by gaining an understanding of what the search engines feed on, and adjusting your web presence accordingly. Also you can also link your social sites to create a positive social stream in applications such as Friendfeed which will help to create a more meaningful river (Leaver, 2010). Identity in the era of 2.0, as described by Helmond (2010, p. 22), is "always under construction, never finished, networked, user-generated, distributed and persistent".
References
Helmond A. (2010). Identity 2.0: Constructing identity with cultural software. Anne Helmond. New Media Research Blog. Retrieved from http://www.annehelmond.nl/wordpress/wp-content/uploads//2010/01/helmond_identity20_dmiconference.pdf
Leaver T. (2010). Social me(dia) rivers [iLecture]. Retrieved from http://lms.curtin.edu.au/