FOSS gamedev and creative worlds

Which one is best to use?
At the moment I am using v6 and the Ethereal Mod.
Do I have to pick v7 to use Ethereal or does it force the game to use v7?

I am bit confused.
Thanks.

Anyone?

If you are using ethereal, you have to choose mg v7, its designed for that.

v6 is generally the default mapgen for your own worlds since it has simple biomes and tree's and flowers, but if you want to make your own mapgen or use a mod mapgen then v7 is used...