Unsatisfactory Q&A - Dojo sounds like it is far less complete than the presentation suggested - heat dissipation, bandwidth, and scheduling are all really important issues that it seems they are far from solving (According to one author the total dissipated power for a single one of their chip packages would apparently be more heat than a single rack could handle, let alone 12 of them in a rack as suggested by the presentation).
It sounds like most of the tasks they need to do though are fairly independent of each other (mostly video processing for training) so the scheduling and internode bandwidth aren't really important for that.