Derick Rethans has followed suit and posted his slides for his presentation from the New York PHP Conference covering XDebug.

His talk, "Efficient Debugging with XDebug" taught how to detect and debug scripts with the help of XDebug. It starts with some background on the application's internals followed by a look at how it uses stack/function traces, dumps of variables, and modified PHP functions to find th problems in your app. He also gives an example of how to use the software to find bottlenecks in scripts with the help of the profiler.

This latest talk can be grabbed directly from his talks page and here [pdf]