Here's another talk by Brian Goetz at this year's JavaOne, this time about the technical details of lambdas in Java (as the title also suggests). Goetz explains why and how invokedynamic (indy - as they apparently call it at Oracle) is just the perfect match to deal with lambdas in the jvm: it's the best instrument for being able to divorce the language construct and the binary representation, so that it's not pinned down till the end of times.