Well, the guy Mark who owns Bass Direct said in Guitar and Bass magazine last month, "The reality is that, if you are playing contemporary pop/party music from the 70`s onwards, you really benefit from using a 5 string bass."
He also says he can see the 4 string, e-g bass becoming obsolete. A bit of a sweeping statement in my view but everyone has their own opinions.
The five string seems to have a bright future but not for me.