Although feedback is often seen as a critical component of the learning process, many open questions about how specific feedback features contribute to the effectiveness of feedback remain--especially in regards to peer feedback of writing. Nelson and Schunn (2009) identified several important features of peer feedback in their nature of feedback model. In the current study, we test an updated theoretical model that includes a broader set of features and considers not only students' likelihood of implementing a comment but also the quality of their revisions. To empirically test the updated theoretical model, we analyze over 7,500 comments from 351 reviewers to 189 authors. Each comment was coded for the presence of praise, a problem description, a suggested solution, localization, focus (i.e., low prose, high prose, substance), implementation, and revision quality. To account for the cross-classified nesting of data, we used a 2-level, cross-classified, hierarchical logistic regression model. Only 2 feedback features increased students' likelihood of implementation (i.e., overall praise and localization), while several feedback features reduced students' likelihood of implementation (i.e., mitigating praise, solutions, and high-prose comments). Overlapping feedback features affected students' ability to revise and in opposing directions from their effect on likelihood of implementation: Revisions were less likely to improve the quality of their paper when implementing comments that included a specific location in the text, but they were more likely to improve the quality of their paper when implementing comments that focused on high-prose and substance issues. Implications of these findings are discussed.