Right now this is still a rumor, so take it with the usual grain of salt. There is speculation that the iPad Camera Connection Kit might allow USB audio output, since it’s offering you a USB port. If true, it’s an interesting development.
It might even allow you to connect some useful devices to the iPad. It also might allow you to charge your USB devices from it, like your Mifi. Then again, we are just dreaming right now. We’ll see what happens.