Chelsio, makers of 10GigE/TOE (TCP Off Load) hardware have posted a paper comparing 10GigE/TOE with Myrinet and Infiniband. Before you dismiss this as another vendor paper, consider that the tests were done by Los Alamos and Ohio State. And what did they find? 10GigE/TOE is looking pretty strong against the other guys. They even used PVFS to test the interconnects. Other papers are available as well.