And lambdas (or similar) has existed in C#, Python, Scala, Javascript and other languages for years. I still thinks this means that those languages has had large benefits compared to Java (7 and older). Now that Java 8 has lambdas even Java developers can learn to write better and more readable code. I also thinks that Java 8 is good enough for most projects now but Java 7 wasn't. Just my thinking.
But that's orthogonal to my point, which is that lambdas offer significant improvements to readability because they remove the irrelevant cruft and simplify the code.