This has nothing to do with yesterday's article about the new fluid system in Blender. Instead it explains how to create realistically animated water surfaces using (animated) texturemaps.
The results are really convincing; start off by checking out the video samples at the end of the tutorial. Don't you just love how you can get away with faking such effects? Imagine having defined a *really* fine mesh and then applying heaps of wave effects to it.
You can find the tutorial here.