Doug Eadline over at Linux Mag predicts that its time for 10 GbE to move into HPC in a serious way
My 10 GigE prediction is based on the following rule of thumb, Speed, Simplicity, Cost, pick an two. I believe 10 GigE will win because of simplicity and cost. IB is already faster and has better latency and if you need this level of performance you are not even looking at Ethernet direction. The joy of clustering is that one size does not fit all and you can build your cluster around your needs.
More in the article, and don’t head over there thinking that Doug has positioned himself in a “10 GbE is the bestest network ever for everything so there” kind of argument. The article is a good read.