While this is interesting news, it isn't a break through at all.. Less than 1% of the Caucasian population is immune to the HIV virus, so the people that had the bone marrow transplants happened to have gotten them from someone who was immune. Your bone marrow is responsible for creating white blood cells, so the bone marrow from the donors created white blood cells that annihilated the virus in the patients.
The thing is, with further research they may be able to synthesize whatever effect the bone marrow transplant had.
The trouble if they
do find a cure for HIV or AIDS, though, is that as everybody goes "whoo-hoooo" and 'parties' to celebrate, all the B-List STDS are going to seize their chance to spread around. Not to mention the population crisis caused by the amount of new pregnancies, the other 'side effect' of unprotected sex that we all like to forget about!