imu_filter_madgwick not publishing on imu/data

edit

Running the sample bag-file "ardrone_imu.bag", I am remapping the topic "/ardrone/imu" to "/imu/data_raw" since according to http://wiki.ros.org/imu_filter_madgwick , that is the nodes subscribed topic. I run the filter with:

rosrun imu_filter_madgwick imu_filter_node _use_magnetic_field_msg:=false _publish_debug_topics:=true

Looking at rostopic list -v and rostopic info on the topics I see that the /Imufilter is subscribing on /imu/data_raw and the /imu/data_raw topic seems fine when echoing it. But when I echo /imu/data where the fused orientation is supposed to be, nothing appears. I can't see any debug topics publishing either. What am I doing wrong here?

$ rostopic list -v

Published topics:
 * /imu/rpy/raw [geometry_msgs/Vector3Stamped] 1 publisher
 * /ardrone/mag [geometry_msgs/Vector3Stamped] 1 publisher
 * /imu/data [sensor_msgs/Imu] 1 publisher
 * /rosout [rosgraph_msgs/Log] 2 publishers
 * /tf [tf2_msgs/TFMessage] 1 publisher
 * /ImuFilter/parameter_descriptions [dynamic_reconfigure/ConfigDescription] 1 publisher
 * /clock [rosgraph_msgs/Clock] 1 publisher
 * /rosout_agg [rosgraph_msgs/Log] 1 publisher
 * /ImuFilter/parameter_updates [dynamic_reconfigure/Config] 1 publisher
 * /imu/magnetic_field [sensor_msgs/MagneticField] 1 publisher
 * /imu/rpy/filtered [geometry_msgs/Vector3Stamped] 1 publisher
 * /imu/data_raw [sensor_msgs/Imu] 1 publisher

Subscribed topics:
 * /imu/magnetic_field [sensor_msgs/MagneticField] 1 subscriber
 * /imu/mag [geometry_msgs/Vector3Stamped] 1 subscriber
 * /rosout [rosgraph_msgs/Log] 1 subscriber
 * /imu/data_raw [sensor_msgs/Imu] 1 subscriber

and

$ rostopic echo /imu/data_raw
  header: 
      seq: 3691
      stamp: 
        secs: 1352907263
        nsecs: 373922350
      frame_id: ardrone_base_link
    orientation: 
      x: 0.149071718242
      y: 0.115987049271
      z: -0.981395641479
      w: 0.0344560895747
    orientation_covariance: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]
    angular_velocity: 
      x: -0.265703596544
      y: 0.275929386036
      z: 0.0895630139048
    angular_velocity_covariance: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]
    linear_acceleration: 
      x: 0.448720367998
      y: 0.806759922206
      z: 8.29265825748
    linear_acceleration_covariance: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]

and

$ rostopic info /imu/data_raw
Type: sensor_msgs/Imu

Publishers: 
 * /player (http://user:44850/)

Subscribers: 
 * /ImuFilter (http://user:38581/)