Not so much. Trust metrics (underpinning Google's PageRank) are pretty efficient at this sort of thing. If people A-Q all vote each other up, but nobody votes them up, their weighted effect is pretty close to nil.

Try: http://en.wikipedia.org/wiki/Trust_metric http://en.wikipedia.org/wiki/PageRank and http://www.advogato.org/trust-metric.html for a bit of an overview.