Incorrect links on the wiki give 404 errors.
Looks like some of the links on the wiki are obsolete. For instance:
http://wiki.ros.org/imu_drivers links to http://docs.ros.org/api/sensor_msgs/html/msg/Imu.html but should link to http://docs.ros.org/fuerte/api/sensor_msgs/html/msg/Imu.html instead.
It appears to be the case with all the API links on that page at least:
http://docs.ros.org/api/std_msgs/html/msg/Bool.html is also a 404.
I haven't checked the other wiki pages yet.