Well those parcels of rice you get at yumcha, aka sticky rice are made from glutinous rice, sunure as to what the black variety would taste like? Maybe like brown rice?!?
If you want to use rice as an adjunct, i would just use plain old long grain as its flavour neutral or the vietnamese broken rice, as its the same then just borken down so it cooks a bit quicker and you will probabaly get a better conversion as more of the starch is exposed.
At my local asian grocer they have bags of mixed rice, like 4-5 different grains.. im temped to try a beer with 1 kg of this but the only thing holding me back is the 'wild rice' in it as when you cook it in a rice cooker it leeches colour and turns the rrest of the rice pinkish..