Hi, not sure how many of you are familiar with these two programs. I've been using L3DT for as long as I remember, but only recently I found out about World Machine.
After running couple of tests I have to say that this combination is really blowing the hair outta my head. As L3DT has always been really easy to use for the generation of 'basic' landscapes, but with every single bit of information (lightmap, normalmap, heightmap, splats, ...), I've found it hard to generate really interesting or memorable landscapes, unless spending long times on tweaking the design / height map by hand.
This is where the World Machine comes in. This program is intended for the creation of heightmaps only. Basically you create the nodetree which will result in the type of landscape you want, generate the heightmap and then put it into L3DT to calculate textures, lights, water and what not.
Both programs are ridiculously cheap.
http://www.bundysoft.com/L3DT/http://www.world-machine.com/index.html---------------------
www.studiohorisen.com