Reductionist Neo-Darwinism is not the only game in town. Evolutionary Biologist Lynn Margulis has studied the processes of evolution at the cellular level and has promoted Symbiogenesis. From the Wikipedia:
She later formulated a theory to explain how symbiotic relationships that are taking place in modern day humans and animals are the driving force of evolution. Genetic variation is proposed to mainly occur as a result of transfer of nuclear information between bacterial cells or viruses and eukaryotic cells. While her organelle genesis ideas are widely accepted, symbiotic relationships as a current method of introducing genetic variation is somewhat of a fringe idea. However, examination of the results from the Human Genome Project lends credence toward an endosymbiotic theory of evolution—or at the very least Margulis's endosymbiotic theory is the catalyst for current ideas about the composition of the human genome. Significant portions of the human genome are either bacterial or viral in origin—some clearly ancient insertions, while others are more recent in origin. This strongly supports the idea of symbiotic—and more likely parasitic—relationships being a driving force for genetic change in humans, and likely all organisms. It should be noted that while the endosymbiotic theory has historically been juxtaposed with Neo-Darwinism, the two theories are not incompatible and the truth is likelier to be that natural selection works on many levels (genetic up to the ecosystem) and variation is introduced both at the genetic and the cellular level.
So, anthropocentrism aside, HIV is likely to be a factor in human evolution, much as viral code is today a component of the human genome.
Dave