BOINC is the infrastructure used by volunteer computing projects such as SETI@home and ClimatePrediction.net. The system sends out jobs to be run on people's home computers and collects the result. Handling all this network traffic puts quite a load on the central server. What the CoreGrid demo has done is to combine BOINC with the BitTorrent peer-to-peer data distribution system, so that the load is distributed.
This may not be news to some of you, as the paper was published last year. I like it; it's a simple idea to solve an immediate problem. I've heard of other projects looking at the potential of BitTorrent as well.