With the increasing spread of information technologies and their potential to filter content, some have argued that people will abandon the reading of dissenting political opinions in favor of material that is closely aligned with their own ideological position. We test this theory empirically by analyzing—both quantitatively and qualitatively—Web links among the writings of top conservative and liberal bloggers. Given our use of novel methods, we discuss in detail our sampling and data collection methodologies. We find that widely read political bloggers are much more likely to link to others who share their political views. However, we find no increase in this pattern over time. We also analyze the content of the links and find that while many of the links are based on straw-man arguments, bloggers across the political spectrum also address each others’ writing substantively, both in agreement and disagreement.