Interface design and the selection of appropriate tasks for small-screen mobile applications are issues critical for mobile commerce. Our earlier research has identified five major task factors that may influence user intention to use handheld devices for wireless applications. These factors are: perceived ease of use, perceived usefulness, perceived playfulness, perceived task complexity, and perceived security. We followed up with a questionnairebased empirical study to validate the relative impact of these proposed task factors on user intention to use handheld devices for mobile commerce. This paper confirms significant correlations between the task factors and user intention. However, only three of the five factors -- perceived usefulness, perceived security, and perceived playfulness -- are important to user intention, explaining 30% of the variations in a multiple regression model. This study makes a unique contribution to HCI and MIS research by providing empirical evidence of user perception of task characteristics for mobile commerce.