I'm on my third fortress right now, and this time I decided to go all-out and head straight for the magma so I could easily make steel. Heck yeah. My fortress is huge and awesome, and none of the various monsters have been able to touch me yet. I'm still waiting for a goblin siege or some magma men, but so far nothing!
Here's my current fortress Ducimalis. This is the first time I've made it to the magma, and I dug straight for it, getting my magma smelter up and running during my first winter. So far the chasm and river monsters haven't caused me many problems, and I haven't seen any magma men. My economy is booming, and I really need more dwarves to help me expand further!