I just put a post up over at Scientific Blogging (which is a really great site, by the way), discussing some of the research into our perceptions of our own social skills.
It appears that people, especially people with higher levels of social anxiety, tend to overestimate how nervous they seem to other people. In a few different social situations, people think they have performed worse than independent observers think they did. In one study, observers actually could not tell which people had high anxiety and which had low (this study was done on children).
Pretty good news, and yet another example of our many perceptual biases. Read the full article here (and also see a picture of me, if you’re curious).