There’s a new official Android SDK available that was released this past week. It is basically Eclipse 3.8 + Android Developer Tools (ADT) 21, pre-installed in a single downloadable package. Previously, Android programmers had to go through a multi-step process to locate the ADT update site, accept licenses, etc. This should save time for new installs. If you’ve got a working setup, I’d stick with that for now, but just update your ADT to version 21.