Props to you onstagebuffnaked for what you're doing. This clinical trial is a great cause and it's awesome that you're participating. The development of an HIV vaccine has been a great challenge over the years because of the "sloppy" replication that HIV is famous for. If you could take a look at the phylogeny, there would probably be hundreds of distinct HIV viruses!
Despite the great cause, I can't exactly say I have high hopes for this trial; if anything it will help researchers understand the virus a little more. I think the future of HIV prevention lies in gene therapies. HIV's main path of entry into our T-cells is through the CCR5 receptor. In Africa, where HIV is very prevalent, researchers have noticed that because of selection, newborn children within the given population have an extremely diminished CCR5 receptor counts, making them "almost immune" to the HIV virus. Since the CCR5 receptor has no essential roles for life, a gene therapy could be developed to suppress the expression of the receptor making it very difficult for people to contract the virus. Such a therapy would even be passed down to offspring. Now this method isn't full proof since there are other receptors HIV can use to enter the cell (CXCR4)... but its a good start :-)
Wow... I probably could have started a whole new thread with that, but good luck and let us know how it turns out!