AMD underlines that Brazos 2.0 and Brazos do not support dual graphics, but the new Kabini platform does. Kabini needs DDR3 memory to run and it can support three upcoming mobile / discrete graphics cores.
AMD has yet to launch most of them, but it says that Kabini is compatible with Seymour XT mobile discrete graphics product that will end up with Radeon HD 8400M series brand. The faster variant will use Sun UL, PRO or XT graphics card for Crossfire and they will come with HD 8500M or HD 8600M brands.
The fastest of them all is Mars 128 LP, PRO or XT that comes with HD 8700M series. AMD now calls it Crossfire dual graphics, and I guess that Crossfire brand remains reserved for two discrete graphics cards coupled together.
Mixing and matching integrated graphics with discrete will however remain known as dual graphics or dGPU as AMD sometimes refers to it.