Doing research online does not excuse a researcher from following ethical protocols or filing IRB applications.
Eysenbach, G., & Till, J. (2001). Information in practice: Ethical issues in qualitative research on Internet communities. British Medical, 323, 1103-1105.
The Kenyon IRB likes to see the following in an online survey:
Online Survey Consent Example (Survey Monkey)
Informed Consent Example (for a Web based study from Social Psychology Network)