There is a very interesting thread and video about this HERE talking about leaving your child rear facing for as long as possible. Izzy is 7 1/2 mths and we will keep her rear facing for as long as possible.

Ezz - in the thread and video it discusses that they may get leg injuries, in a serious accident, however that is preferable to losing their lives as a result of not having a strong neck in a front on accident. Horrible to think about though isn't it.