I think it's much more subtle than that. 'Powered' is a poor metaphor I think. I believe what they're referring to is the actual reverse transcription process. Retroviruses carry its own reverse transcriptease, and must use the cell's own resources to do the actual transcription (they need to get the dNTP to build actual DNA strands). The 'big deal' about this discovery is that HIV can use rNTP to preform reverse transcription instead in cases where there isn't enough dNTP, which presumably (I'm not an expert in this field) is one of the reasons why it is so successful compared to other retroviruses.
A retrovirus is an RNA that uses the host to make it's corresponding DNA.
White blood cells--which HIV takes over--don't contain DNA building blocks (dNTP) because white blood cells don't replicate. So HIV can't make it's corresponding DNA.
Instead, it just replicates using rNTP to produce more RNA. I think (correct me if I'm wrong) rNTP is available because it's used in ATP synthesis.