Rhetorics of Web 2.0 emphasize the sharing of user generated content. But how much content is actually openly shared? Is the Web really an open arena for content, or more suited to sharing in small groups? Will sharing change as more people become aware of potential legal and social pitfalls? Will media services increasingly be used for personal archive? As designers, we need to understand how individuals are making decisions about what to share, and with whom to share. We need to be cognizant of possible differences in social and cultural norms among different populations. We present a sketch of sharing defaults on a number of well-known social sites, and of user practices in a photo-sharing, social networking site, Flickr. Our project is in its first phase, intended to scope a broader study of sharing practices and drive application design ideation.