I've been watching some very excited tweets go past about concurrency improvements in .NET 4.0.  I've got to say, I'm quite looking forward to hearing about this once the NDAs drop away (not an MVP, nor am I likely to be).  Retlang is pretty much the only game in town for concurrency right now, and it's quite hard explaining to people the problem it's trying to solve.  The standard question is "what's wrong with using Threads"?  The work the Maestro team is doing looks exciting as well, although I'm a bit dubious about the benefits of a language rather than...