Jeremy Gibbons explains categories, focusing on them as an organizing principle helpful in managing generic libraries.
Craig Walls presents some of the features supported in Spring 4 including WebSockets, REST controllers, conditional configuration, ordered list injection, compatibility with Java 8 and Java EE 6&7.
Erik Meijer introduces covariance and contra-variance with real world examples.
Bjarne Stroustrup keynotes on what C++ is in general, how C++ 11 makes simple things even simpler, resource management, generic programming, and concurrency.
Ola Bini attempts to answer a few questions: Why are new languages still being created, Is it worth choosing languages strategically, and Does language actually matter?
Andrei Alexandrescu discusses generic programming, showing how to solve generic tasks with D, tasks that are difficult or impossible to perform with other languages.