In-home sensing and inference systems impose privacy risks and social tensions, which can be substantial barriers for the wide adoption of these systems. To understand what might affect people's perceptions and acceptance of in- home sensing and inference systems, we conducted an empirical study with 22 participants from 11 households. The study included in-lab activities, four weeks using sensor proxies in situ, and exit interviews. We report on participants' perceived benefits and concerns of in-home sensing applications and the observed changes of their perceptions throughout the study. We also report on tensions amongst stakeholders around the adoption and use of such systems. We conclude with a discussion on how the ubicomp design space might be sensitized to people's perceived concerns and tensions regarding sensing and inference in the home.