I finally tried it. Doing virtually nothing at all, I ended up with this terrain as a random seed (I added some water), and then use a tutorial to modify the terrain surface with rocks and grass and then with snow. I am truly impressed. Total time to do this was mere minutes. I rendered the originals in 800x600 and rendering was under 5 minutes.
Now, let it be said, that the application is still in development. Some plugins are available, but I am still looking for a utility that permits me to import a LW object. Also, as you can see, trees are still in its future. In any case, until then I plan to enjoy this awesome freebie as is.
Download it here: http://www.planetside.co.uk/terragen/