Online vs. offline research
It's interesting to consider how internet based research is different from more traditional, offline research. As noted in the article by Wright, some of the greatest worries about internet research is whether or not we can get a representative sample and whether it's possible to ensure the validity of participants. Although I get why there might be some increased concern with these issues for online studies, in most ways offline studies suffer from the same problems. For example, trying to get a representative sample of gay men to take a traditional paper-and-pencil survey isn't very possible since we really don't have a good estimate of the number of gay men in the US and how they're distributed. Offline studies also suffer validity problems, especially is participants aren't required to complete an interview face-to-face (e.g., completing a survey and sending it in). Whether participants are completing surveys online or offline, they can always lie or distort their answers. So, it seems like a lot of attention is being paid to the possible pitfalls of Internet research, but honestly traditional self-report survey methods seem just as problematic.
Both Laura and Turkle brought up the issue of protecting participant confidentiality regarding online postings. Although good practice to minimize any harm to participants when possible, I do think it's also important to be able to cite the actual source where possible since the source is the foundation upon which good scientific evidence is based. If we aren't certain of the veracity of the source, it's a little hard to establish scientific credibility.