Here in Nevada the law is simply "You must have a front license plate unless you are driving an older vehicle not equipped to mount a front license plate."
So I don't use a front license plate because my vehicle is "older" (I love how they don't specify how old is "old") and the mounting bracket is broken (thus, my vehicle at the moment is not equipped to mount a front license plate.
I've got the broken bracket and the front plate in the trunk just in case I need to be "just on my way" to get it fixed...
So far no problems with the law, and it looks a heck of a lot better with no plate.