Hm, now this is an interesting PoD...
Personally, IMO Africa would be in a much better shape than it is OTLy. OTLy, I've heard people saying that there are two diseases which mean that Africa cannot match Asia in terms of development - malaria and AIDS. Now, both of those diseases exist in Asia as well as in Africa, but in both cases they are far more prevelent in Africa than they are in Asia. Eliminating one of those two diseases would seem likely to open the way for greater African development and for a more stable Africa.
The ripple effects of those changes are hard to guage - for one thing, Somalia could wind up stable enough that there would be no need for a US intervention, no Black Hawk Down or anything like that. If that were the case, then perhaps there would have been more hesitance on the part of terrorists to target US assets, since it has been argued that many Islamic extremists were convinced after what he saw in Somalia that the USA was weak and would not properly retaliate for attacks against its citizens and military.
Additionally, although the levels that this effect might reach cannot be determined, with no AIDS perhaps stronger and more orderly African governments might do something about malaria, at least to a greater extent than they OTLy did. Regardless of how extensive the effects of this are, it seems impossible to argue that the absence of AIDS in Africa will have any economic effect other than one that leads to greater economic growth.
In the western world, well, I don't know much about music or theater, but many famous and respected performers perished as a result of the disease, so I can only assume that the cultural situation would be different from how it developed OTLy. There could be greater support for gay rights as well, although how much of a change that would be is hard to say. There would probably still be something of a conservative backlash against '60s values, but it could well prove weaker than it OTLy was. Again, it's hard to say. Almost undoubtedly, there would be less of a stigma attatched to casual sex, although there would undoubtedly remain some sort of stigma.
Well, those are my thoughts on this, at any rate.