Correcting myself re. concurrency at Lang.NET, there was one "sit up and take notice" discussion. Erik Meijer briefly discussed that he and his team have implemented (or at least prototyped) MapReduce for LINQ. "We call it MapReduce for Datacenters or somesuch..."
I asked him to clarify if this a part of Volta or a separate project or been discussed and he said they hadn't talked about it yet. He made it sound like it was something they did in their copious spare time. During the talk, he'd said "I come into work every day and hack. Who would want a job like mine?" to which 45 people in the room had to bite their lips to prevent themselves shouting "Me!"