Not, on the whole, a very good article. The concepts are not well explained - either the writer does not truly understand them or his language skills are not adequate to the task.

IAC, the example is a simple 'fire and forget' one - in most real-world scenarios the async method would not be void - a Task() or Task T would be passed on completion.

IMO the standard MSDN documentation does a better job : http://msdn.microsoft.com/en-us/library/hh191443(v=vs.110).aspx and this does the best : http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=23753