Number of incidents posted on wiihaveaproblem: 214
Number of wiis sold worldwide: 6.03 million
Chances of wiimote related catastrophe (estimated): 1 in 27,000.
According to
this site, those odds are slightly greater than dying in a bicycle accident, and slightly lower than dying in while playing soccer (football..?) in Britain.
Also, do keep in mind that a lot of the recorded incidents occured before Nintendo beefed up the straps. The newer ones have a much lower chance of being broken.