The rest of the world seems to use DVB for everything.
Here we have QAM for cable and 8VSB for Terrestrial / Antenna and several flavors for Satellite.
Not always, lots of the standards set up by the US are first and by the time the rest of the world gets around to using something similar they opt for something simpler or of course something that is an open standard. We up here in Canada are usually stuck with whatever the US decides in order to make us compatible.
Digital radio uses IBOC in the US and Canada originally decided on DAB but then backpedaled and decided to use IBOC so as not to have problems. It would suck it you drove to the US and couldn't get any digital radio in your car I guess.