I looked into this specificaly with voting a while ago 656735 and found that there was a significant advantage network wise. Its hard to say from that what the advantages would be for processor time etc without someone more familiar with the server. It should also be easy enough to adapt to submit all votes on the page via AJAX at once instead once for each vote. (That code is 2 years old so please don't laugh at me, i havn't looked at it or used it in ages)