One of the changes we've made for the final public build is that we've greatly reduced the costs or raising and lowering land.
Now, you can't use these spells to create mountains or make islands. That's not their purpose. What they can do, however is create shorter routes through mountain regions (lower land) and connect players to other parts of the world that aren't normally accessible (raise land).
This will become a particularly big deal after release when we start releasing map packs to supplement the random maps. In these map packs, the players (AI and human) will be able to explore larger areas if they make use of these spells (i.e. goodies and special quests hidden behind mountains OR by island hopping).
Here's a video that shows this off:
Elemental: Fallen Enchantress will be released on October 23!