They are an interesting group. They are not Christian -- they don't hold a trinitarian belief. Rather, they trace their founding to John the Baptist. They are monotheist but are not Muslim. They may have an historical connection to the Ebionites. There are doctrinal similarities between the Mandaeans/Sabaeans and the Qumran community described in the Dead Sea Scrolls. The theory is that after the destruction of the community along the temple at the hands of the Romans in 70 C.E., these groups dispersed eastward. It is believed that they, along with Judaism and Christianity, had an influence upon the religious views of Mohammad. They still exist today, primarily along the Euphrates River in Iraq, but also in scattered communities elsewhere.
I can't imagine there are too many of them in Iraq today. Kinda like that small Jewism community in Baghdad that stretched back to the Babylonian captivity. I think the report talked about 2-3 dozen survivors with one in her 30's, but most unlikely to survive the next several years.