19. A apparatus for recognizing a gesture, the apparatus comprising: means for determining a first set of metrics to differentiate gestures from among only a first subset of gestures of a plurality of gestures, the first subset of gestures recognizable as valid input in a particular context of a user interface environment; means for receiving user input that causes a gesture classification context to be applied from a plurality of gesture classification contexts that are available for a means for gesture analysis, wherein the gesture classification context indicates the first subset of gestures; means for applying the gesture classification context to the means for gesture analysis; means for receiving data indicative of the gesture performed by a user after applying the gesture classification context; and means for, based on the first set of metrics, identifying using the means for gesture analysis, the gesture in accordance with the applied gesture classification context, wherein identifying includes identifying the gesture from only the first subset of gestures of the plurality of gestures indicated by the applied gesture classification context while the gesture classification context is applied; means for receiving an indication of a second subset of gestures from the plurality of gestures, wherein each gesture of the second subset of gestures is valid in a second gesture classification context; means for calculating a second set of metrics for the second subset of gestures to differentiate gestures from among only the second subset of gestures, wherein: only the second subset of gestures are eligible to be identified when the second gesture classification context is applied, and at least one gesture of the second subset of gestures is not in the first subset of gestures; means for receiving user input that causes the second gesture classification context to be applied to the means for gesture analysis; means for receiving data indicative of a second gesture performed by the user after applying the second gesture classification context; and means for identifying, based on the second set of metrics, the second gesture in accordance with the applied second gesture classification context, wherein identifying includes identifying the second gesture from only the second subset of gestures indicated by the applied second gesture classification context.
19. A apparatus for recognizing a gesture, the apparatus comprising: means for determining a first set of metrics to differentiate gestures from among only a first subset of gestures of a plurality of gestures, the first subset of gestures recognizable as valid input in a particular context of a user interface environment; means for receiving user input that causes a gesture classification context to be applied from a plurality of gesture classification contexts that are available for a means for gesture analysis, wherein the gesture classification context indicates the first subset of gestures; means for applying the gesture classification context to the means for gesture analysis; means for receiving data indicative of the gesture performed by a user after applying the gesture classification context; and means for, based on the first set of metrics, identifying using the means for gesture analysis, the gesture in accordance with the applied gesture classification context, wherein identifying includes identifying the gesture from only the first subset of gestures of the plurality of gestures indicated by the applied gesture classification context while the gesture classification context is applied; means for receiving an indication of a second subset of gestures from the plurality of gestures, wherein each gesture of the second subset of gestures is valid in a second gesture classification context; means for calculating a second set of metrics for the second subset of gestures to differentiate gestures from among only the second subset of gestures, wherein: only the second subset of gestures are eligible to be identified when the second gesture classification context is applied, and at least one gesture of the second subset of gestures is not in the first subset of gestures; means for receiving user input that causes the second gesture classification context to be applied to the means for gesture analysis; means for receiving data indicative of a second gesture performed by the user after applying the second gesture classification context; and means for identifying, based on the second set of metrics, the second gesture in accordance with the applied second gesture classification context, wherein identifying includes identifying the second gesture from only the second subset of gestures indicated by the applied second gesture classification context. 23. The apparatus for recognizing the gesture of claim 19 , wherein: the determining the second subset of gestures from the plurality of gestures and the determining calculating the second set of metrics for the second subset of gestures to differentiate gestures from among only the second subset of gestures occur in response to an application being installed on the computer system.