As you may have seen from previous posts, I have been covering Lang.NET and some of the interesting things that came from it. I've always been interested in compilers, DSLs and such, and I hope you found them interesting as well. I covered it these posts here:
Anyhow, they have finally posted the videos from Lang.NET and are now available here for your review. They have the talks from Anders Hejlberg for C#, Luke Hoban from F#, John Lam for IronRuby, Roman Ivantsov for Irony, Tomas Petricek for Phalanger and F# and so on. Go and check them out. Pretty cool stuff!