The Xbox 360 is banned in China. As is the PlayStation 3. In fact, most consoles are banned in the world's most populous nation, with the exception of a select few. Like the Nintendo 3DS.
As it has with previous pieces of hardware — like the DS — Nintendo has been able to secure a Chinese release (through its partnership with iQue) for its upcoming gaming handheld, with the 3DS due out there in April.
It'll be branded the iQue 3DS. The iQue DS had unique copy protection that meant Chinese games could only be played by Chinese systems (though Chinese systems could play everywhere else's games); it remains to be seen whether the iQue 3DS will continue this practice.