This article suggests the idea of adapting the basic idea of PageRank (the search algorithm at the centre of Google) into the problem space of voting.
I like this idea.
It’s very similar to what we have been proposing in Polly (http://pirateparty.org.au/wiki/Polly/High_Level_Requirements#Principle:_To_each_his_own) , but seems to be suggested as a more direct/immediate action.
i.e. When you vote, you can vote Yay/Nay and/or you could refer to someone who’s knowledge of the subject you respect and thereby delegate to them on this occasion.