The U.S. government will never shut down fully unless there is an armed revolution outside the doors of 1600 Pennsylvania Avenue. A new budget deal will keep the government operational until early 2015. The most recent shutdown shuttered non-esssential services for a few weeks, but didn't completely shutdown the normal operation of Uncle Sam.
The US government already did shut down... but, it probably won't again. Not for the foreseeable future. The only way that would happen is if there was another headbutting match going on over ridiculous things, like not wanting people to have health care, but there's no telling what a headbutting match can be started over next. Better energy? Stopping global warming?